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lvm2/test/shell/pvmove-cache-segtypes.sh

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2017-07-02 22:38:32 +03:00
#!/usr/bin/env bash
# Copyright (C) 2014 Red Hat, Inc. All rights reserved.
#
# This copyrighted material is made available to anyone wishing to use,
# modify, copy, or redistribute it subject to the terms and conditions
# of the GNU General Public License v.2.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
test_description="ensure pvmove works with the cache segment types"
SKIP_WITH_LVMLOCKD=1
. lib/inittest
# pvmove fails when a RAID LV is the origin of a cache LV
# pvmoving cache types is currently disabled in tools/pvmove.c
# So, for now we set everything up and make sure pvmove /isn't/ allowed.
# This allows us to ensure that it is disallowed even when there are
# stacking complications to consider.
which md5sum || skip
aux have_cache 1 3 0 || skip
# for stacking
aux have_thin 1 8 0 || skip
aux have_raid 1 4 2 || skip
aux prepare_vg 5 80
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
for mode in "--atomic" ""
do
# Each of the following tests does:
# 1) Create two LVs - one linear and one other segment type
# The two LVs will share a PV.
# 2) Move both LVs together
# 3) Move only the second LV by name
# Testing pvmove of cache-pool LV (can't check contents though)
###############################################################
lvcreate -aey -l 2 -n ${lv1}_foo $vg "$dev1"
lvcreate --type cache-pool -n ${lv1}_pool -l 4 $vg "$dev1"
check lv_tree_on $vg ${lv1}_foo "$dev1"
check lv_tree_on $vg ${lv1}_pool "$dev1"
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
pvmove $mode "$dev1" "$dev5" 2>&1 | tee out
lvs -a -o+devices $vg
check lv_tree_on $vg ${lv1}_pool "$dev5"
check lv_tree_on $vg ${lv1}_foo "$dev5"
lvremove -ff $vg
dmsetup info -c | not grep $vg
# Testing pvmove of origin LV
#############################
lvcreate -aey -l 2 -n ${lv1}_foo $vg "$dev1"
lvcreate --type cache-pool -n ${lv1}_pool -l 4 $vg "$dev5"
lvcreate --type cache -n $lv1 -l 8 $vg/${lv1}_pool "$dev1"
check lv_tree_on $vg ${lv1}_foo "$dev1"
check lv_tree_on $vg ${lv1}_pool "$dev5"
check lv_tree_on $vg ${lv1} "$dev1"
aux mkdev_md5sum $vg $lv1
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
pvmove $mode "$dev1" "$dev3" 2>&1 | tee out
check lv_tree_on $vg ${lv1}_foo "$dev3"
#check lv_tree_on $vg ${lv1}_pool "$dev5"
lvs -a -o name,attr,devices $vg
check lv_tree_on $vg ${lv1} "$dev3"
#check dev_md5sum $vg $lv1
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
#pvmove $mode -n $lv1 "$dev3" "$dev1"
#check lv_tree_on $vg ${lv1}_foo "$dev3"
#check lv_tree_on $vg ${lv1}_pool "$dev5"
#check lv_tree_on $vg ${lv1} "$dev1"
#check dev_md5sum $vg $lv1
lvremove -ff $vg
dmsetup info -c | not grep $vg
# Testing pvmove of a RAID origin LV
####################################
lvcreate -aey -l 2 -n ${lv1}_foo $vg "$dev1"
lvcreate --type raid1 -m 1 -l 8 -n $lv1 $vg "$dev1" "$dev2"
lvcreate --type cache -l 4 -n ${lv1}_pool $vg/$lv1 "$dev5"
check lv_tree_on $vg ${lv1}_foo "$dev1"
check lv_tree_on $vg ${lv1} "$dev1" "$dev2"
check lv_tree_on $vg ${lv1}_pool "$dev5"
aux mkdev_md5sum $vg $lv1
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
pvmove $mode "$dev1" "$dev3" 2>&1 | tee out
check lv_tree_on $vg ${lv1}_foo "$dev3"
lvs -a -o+devices $vg
not check lv_tree_on $vg ${lv1} "$dev1"
#check lv_tree_on $vg ${lv1}_pool "$dev5"
#check dev_md5sum $vg $lv1 -- THIS IS WHERE THINGS FAIL IF PVMOVE NOT DISALLOWED
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
#pvmove $mode -n $lv1 "$dev3" "$dev1"
#check lv_tree_on $vg ${lv1}_foo "$dev3"
#check lv_tree_on $vg ${lv1} "$dev1" "$dev2"
#check lv_tree_on $vg ${lv1}_pool "$dev5"
#check dev_md5sum $vg $lv1
lvremove -ff $vg
dmsetup info -c | not grep $vg
# Testing pvmove of a RAID cachepool (metadata and data)
########################################################
lvcreate -aey -l 2 -n ${lv1}_foo $vg "$dev1"
2014-07-11 15:13:56 +04:00
lvcreate --type raid1 -L 6M -n meta $vg "$dev1" "$dev2"
lvcreate --type raid1 -L 4M -n ${lv1}_pool $vg "$dev1" "$dev2"
2014-05-21 00:50:33 +04:00
lvconvert --yes --type cache-pool $vg/${lv1}_pool --poolmetadata $vg/meta
lvcreate --type cache -n $lv1 -L 8M $vg/${lv1}_pool "$dev5"
check lv_tree_on $vg ${lv1}_foo "$dev1"
check lv_tree_on $vg ${lv1}_pool "$dev1" "$dev2"
check lv_tree_on $vg ${lv1} "$dev5"
aux mkdev_md5sum $vg $lv1
# This will move ${lv1}_foo and the cache-pool data & meta
# LVs, both of which contain a RAID1 _rimage & _rmeta LV - 5 total LVs
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
pvmove $mode "$dev1" "$dev3" 2>&1 | tee out
check lv_tree_on $vg ${lv1}_foo "$dev3"
not check lv_tree_on $vg ${lv1}_pool "$dev1"
#check lv_tree_on $vg ${lv1} "$dev5"
#check dev_md5sum $vg $lv1
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
#pvmove $mode -n ${lv1}_pool "$dev3" "$dev1"
#check lv_tree_on $vg ${lv1}_foo "$dev3"
#check lv_tree_on $vg ${lv1}_pool "$dev1" "$dev2"
#check lv_tree_on $vg ${lv1} "$dev5"
#check dev_md5sum $vg $lv1
lvremove -ff $vg
dmsetup info -c | not grep $vg
# Testing pvmove of Thin-pool on cache LV on RAID
#################################################
lvcreate -aey -l 2 -n ${lv1}_foo $vg "$dev1"
# RAID for cachepool
lvcreate --type raid1 -m 1 -L 6M -n meta $vg "$dev1" "$dev2"
lvcreate --type raid1 -m 1 -L 4M -n cachepool $vg "$dev1" "$dev2"
2014-05-21 00:50:33 +04:00
lvconvert --yes --type cache-pool $vg/cachepool --poolmetadata $vg/meta
# RAID for thin pool data LV
lvcreate --type raid1 -m 1 -L 8 -n thinpool $vg "$dev3" "$dev4"
# Convert thin pool data to a cached LV
lvconvert --type cache -Zy $vg/thinpool --cachepool $vg/cachepool
# Create simple thin pool meta
lvcreate -aey -L 2M -n meta $vg "$dev1"
# Use thin pool data LV to build a thin pool
2014-05-21 00:50:33 +04:00
lvconvert --yes --thinpool $vg/thinpool --poolmetadata $vg/meta
# Create a thin lv for fun
lvcreate -T $vg/thinpool -V 20 -n thin_lv
check lv_tree_on $vg ${lv1}_foo "$dev1"
check lv_tree_on $vg cachepool "$dev1" "$dev2"
check lv_tree_on $vg thinpool "$dev1" "$dev3" "$dev4"
aux mkdev_md5sum $vg thin_lv
lvs -a -o name,attr,devices $vg
# Should move ${lv1}_foo and thinpool_tmeta from dev1 to dev5
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
pvmove $mode "$dev1" "$dev5" 2>&1 | tee out
lvs -a -o name,attr,devices $vg
check lv_tree_on $vg ${lv1}_foo "$dev5"
not check lv_tree_on $vg cachepool "$dev1"
check lv_tree_on $vg thinpool "$dev3" "$dev4" "$dev5" # Move non-cache tmeta
#check dev_md5sum $vg/thin_lv
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
#pvmove $mode -n $vg/cachepool "$dev5" "$dev1"
#check lv_tree_on $vg ${lv1}_foo "$dev5"
#check lv_tree_on $vg $vg/cachepool "$dev1" "$dev2"
#check lv_tree_on $vg $vg/thinpool "$dev3" "$dev4"
#check dev_md5sum $vg/thin_lv
2014-05-21 00:50:33 +04:00
lvremove -ff $vg
dmsetup info -c | not grep $vg
pvmove: Enable all-or-nothing (atomic) pvmoves pvmove can be used to move single LVs by name or multiple LVs that lie within the specified PV range (e.g. /dev/sdb1:0-1000). When moving more than one LV, the portions of those LVs that are in the range to be moved are added to a new temporary pvmove LV. The LVs then point to the range in the pvmove LV, rather than the PV range. Example 1: We have two LVs in this example. After they were created, the first LV was grown, yeilding two segments in LV1. So, there are two LVs with a total of three segments. Before pvmove: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- After pvmove inserts the temporary pvmove LV: --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | ------------------------------------- PV | 000 - 255 | 256 - 511 | 512 - 767 | ------------------------------------- Each of the affected LV segments now point to a range of blocks in the pvmove LV, which purposefully corresponds to the segments moved from the original LVs into the temporary pvmove LV. The current implementation goes on from here to mirror the temporary pvmove LV by segment. Further, as the pvmove LV is activated, only one of its segments is actually mirrored (i.e. "moving") at a time. The rest are either complete or not addressed yet. If the pvmove is aborted, those segments that are completed will remain on the destination and those that are not yet addressed or in the process of moving will stay on the source PV. Thus, it is possible to have a partially completed move - some LVs (or certain segments of LVs) on the source PV and some on the destination. Example 2: What 'example 1' might look if it was half-way through the move. --------- --------- --------- | LV1s0 | | LV2s0 | | LV1s1 | --------- --------- --------- | | | ------------------------------------- pvmove0 | seg 0 | seg 1 | seg 2 | ------------------------------------- | | | | ------------------------- source PV | | 256 - 511 | 512 - 767 | | ------------------------- | || ------------------------- dest PV | 000 - 255 | 256 - 511 | ------------------------- This update allows the user to specify that they would like the pvmove mirror created "by LV" rather than "by segment". That is, the pvmove LV becomes an image in an encapsulating mirror along with the allocated copy image. Example 3: A pvmove that is performed "by LV" rather than "by segment". --------- --------- | LV1s0 | | LV2s0 | --------- --------- | | ------------------------- pvmove0 | * LV-level mirror * | ------------------------- / \ pvmove_mimage0 / pvmove_mimage1 ------------------------- ------------------------- | seg 0 | seg 1 | | seg 0 | seg 1 | ------------------------- ------------------------- | | | | ------------------------- ------------------------- | 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 | ------------------------- ------------------------- source PV dest PV The thing that differentiates a pvmove done in this way and a simple "up-convert" from linear to mirror is the preservation of the distinct segments. A normal up-convert would simply allocate the necessary space with no regard for segment boundaries. The pvmove operation must preserve the segments because they are the critical boundary between the segments of the LVs being moved. So, when the pvmove copy image is allocated, all corresponding segments must be allocated. The code that merges ajoining segments that are part of the same LV when the metadata is written must also be avoided in this case. This method of mirroring is unique enough to warrant its own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV (for user created mirrors). The advantages of performing pvmove in this way is that all of the LVs affected can be moved together. It is an all-or-nothing approach that leaves all LV segments on the source PV if the move is aborted. Additionally, a mirror log can be used (in the future) to provide tracking of progress; allowing the copy to continue where it left off in the event there is a deactivation.
2014-06-18 07:59:36 +04:00
done