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The str_list_destroy function may be called to cleanup memory when
the list is not used anymore and the list itself was not allocated
from the memory pool.
When checking minimum mda size, make sure the mda_size after alignment
and calculation is more than 0 - if there's no place for an MDA at the
end of the disk, the _text_pv_add_metadata_area does not try to add it
there and it returns (because we already have the MDA at the start of
the disk at least).
Actually, we don't need extra condition as introduced in commit
00348c0a63. We should fix the last
condition:
(mdac->rlocn.size >= mdah->size)
...which should be:
(MDA_HEADER_SIZE + (rlocn ? rlocn->size : 0) + mdac->rlocn.size >= mdah->size))
Where the "mdac" is new metadata, the "rlocn" is old metadata.
So the main problem with the previous condition was that it
didn't count in MDA_HEADER_SIZE properly (and possible existing
metadata - the "rlocn"). This could have caused the error state
where metadata in ring buffer overlap to not be hit.
Replace the new condition introduced in 00348c0a63
with the improved one for the condition that existed there
already but it was just incomplete.
We're already checking whether old and new meta do not overlap in
ring buffer (as we need to keep both old and new meta during vg_write
up until vg_commit).
We also need to check whether the new metadata do not overlap
themselves in case we don't have old metadata yet (...because
we're in vgcreate). This could happen if we're creating a VG so
that the very first metadata written are long enough that it wraps
themselves in metadata ring buffer.
Although we limited the minimum metadata area size better with the
previous commit ccb8da404d which
makes the initial VG metadata overlap in ring buffer to be less
probable, the risk of hitting this overlap condition is still there
if we still manage to generate big enough metadata somehow.
For example, users can provide many and/or long VG tags during vgcreate
so that the VG metadata is long enough to start to wrap in the ring
buffer again...
This option could never have been printed in lvm2 metadata, so it could
be safely removed as it could have been set only as 0.
These configurable setting is supported via metadata profile.
Now with correctly functioning dmeventd enable usage of
low_water_mark for faster reaction on pool's threshold.
When user select e.g. 80% as a threshold value,
dmeventd doesn't need to wait 10 seconds till monitoring
timer expires, but nearly instantly resizes thin-pool
to fit bellow threshold.
The former patch(dab3ebce4c) is a little bit strict. For example, it is
OK to create PV on unpartitioned DASD devices with LDL formatted. So
after lvm version containing the patch, LVs created on those devices
could not be found.
Signed-off-by: Lidong Zhong <lzhong@suse.com>
Recognize the target only 'extends' and do not enforce
'flush' in this case. Only the size reduction
still requires flush (so disables usage of no_flush flag).
If some other targets do require flush before suspend,
they have to explicitly ask for it.
While the activation code tries to evaluate which target
really needs flush with suspend and which may go without flush,
it has stayed effectively disabled by original commit:
33f732c5e9 since here
it only allows to pass non-pvmoving 'mirrors'.
So remove check for mirror LV type and only disable
no_flush for 'pvmove'..
TODO: Looking into history - it also seemed like raid target
would have always required flushing but it's been later
removed without clean explanation.
If some more targets really do need 'no_flush' it should
been handle at their 'level' - since we now stack multiple
targets over itself.
Use single code to evaluate if the percentage value has
crossed threshold.
Recalculate amount value to always fit bellow
threshold so there are not need any extra reiterations
to reach this state in case policy amount is too small.
Since plugin's percentage compare has been fixed,
it's now revealed wrong compare here.
The logic for threshold is - to allow to go as high
as given value e.g. 80% - so if pool is exactlu 80%
full it's still allowed to use it (dmeventd will not
resize it).
Running "vgremove -f VG & pvs" results in the pvs
command reporting that the VG is not found or is
inconsistent. If the VG is gone or being removed,
the pvs command should just skip it and not print
errors about it.
"Not found" is because the pvs command created the
list of VGs to process, including VG, then vgremove
removed the VG, then the pvs command came to to read
the VG to process it and did not find it.
An "inconsistent" error could be reported if vgremove
had only partially completed removing VG when pvs did
vg_read on the VG to process it, causing pvs to find
the VG in a partially-removed state.
This fix adds a flag that pvs uses to ignore a VG
that can't be read or is inconsistent.
When lvmetad is used and lvmcache update function (lvmcache_update_vgname_and_id)
was called to update existing lvmcache records, a condition was met
which made to retun from the update function immediately, effectively
making it NOOP.
It seems there's no reason for such condition and lvmcache should be
update appropriately even when lvmetad used as lvmcache may be reused,
most notably in lvm shell.
It's possible this is a remnant of the lvmetad development code which
didn't get removed for some reason and the bug didn't get spotted
because lvm shell is not used often (the condition dates back to 2012
or so).
Example, lvmetad and lvm shell used:
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/sda vg lvm2 a-- 124.00m 124.00m
Before this patch:
==================
lvm> vgremove vg
Volume group "vg" successfully removed
lvm> pvs
With this patch applied:
========================
lvm> vgremove vg
Volume group "vg" successfully removed
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/sda lvm2 --- 128.00m 128.00m
The lvmcache info might be resued, most notably in lvm shell.
We need to be sure that even lvmcache_info marked as invalid
is removed from the lvmcache so it does not confuse any subsequent
code/commands executed later on.
Problematic example with the lvm shell:
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/sda lvm2 --- 128.00m 128.00m
Before this patch (/dev/sda still displayed in a way):
======================================================
lvm> pvremove /dev/sda
Labels on physical volume "/dev/sda" successfully wiped
(without lvmetad)
lvm> pvs
No physical volume label read from /dev/sda
(with lvmetad)
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/sda lvm2 --- 128.00m 128.00m
With this patch applied:
========================
lvm> pvremove /dev/sda
Labels on physical volume "/dev/sda" successfully wiped
(without lvmetad)
lvm> pvs
(with lvmetad)
lvm> pvs
Make lvm2_disable_dmeventd_monitoring() more explicit.
As memlock_inc_daemon() is also used by clvmd, which
does changes dmeventd and suspend ignore state at
some stages - make updates of these 2 variable
tied to the call of lvm2_disable_dmeventd_monitoring().
Once this call is made dmeventd monitoring
and suspended devices are ignored.
TODO: all lvm-global settings should really be moved
to command context.
The old code made two loops through the PVs: in the first
loop it found the max PV and VG name lengths, and in the
second loop it printed each PV using the name lengths as
field widths for aligning columns.
The new code uses process_each_pv() which makes one loop
through the PVs. In the *first* call to pvscan_single(),
the max name lengths are found by looping through the
lvmcache entries which have been populated by the generic
process_each code prior to calling any _single functions.
Subsequent calls to pvscan_single() reuse the max lengths
that were found by the first call.
The new report/compact_output_cols setting has exactly the same effect
as report/compact_output setting. The difference is that with the new
setting it's possible to define which cols should be compacted exactly
in contrast to all cols in case of report/compact_output.
In case both compact_output and compact_output_cols is enabled/set,
the compact_output prevails.
For example:
$ lvmconfig --type full report/compact_output report/compact_output_cols
compact_output=0
compact_output_cols=""
$ lvs vg
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
lvol0 vg -wi-a----- 4.00m
---
$ lvmconfig --type full report/compact_output report/compact_output_cols
compact_output=0
compact_output_cols="data_percent,metadata_percent,pool_lv,move_pv,origin"
$ lvs vg
LV VG Attr LSize Log Cpy%Sync Convert
lvol0 vg -wi-a----- 4.00m
---
$ lvmconfig --type full report/compact_output report/compact_output_cols
compact_output=1
compact_output_cols="data_percent,metadata_percent,pool_lv,move_pv,origin"
$ lvs vg
LV VG Attr LSize
lvol0 vg -wi-a----- 4.00m
This reverts commit 1b1c01a27b.
This caused messages to get dropped instead of logged into the log file.
(The log file and log function are independent at the moment.)
Some signatures are spread around the disk in several copies, mainly for
backup. Make libblkid to detect these extra copies - there was missing
"blkid_probe_step_back" fn call after successful wipe of previous signature
copy.
An example with FAT table which has copies:
$ mkfs.vfat /dev/sda1
Before this patch:
$ pvcreate /dev/sda1
WARNING: vfat signature detected on /dev/sda1 at offset 54. Wipe it? [y/n]: y
Wiping vfat signature on /dev/sda1.
Physical volume "/dev/sda1" successfully created
With this patch applied:
$ pvcreate /dev/sda1
WARNING: vfat signature detected on /dev/sda1 at offset 54. Wipe it? [y/n]: y
Wiping vfat signature on /dev/sda1.
WARNING: vfat signature detected on /dev/sda1 at offset 0. Wipe it? [y/n]: y
Wiping vfat signature on /dev/sda1.
WARNING: vfat signature detected on /dev/sda1 at offset 510. Wipe it? [y/n]: y
Wiping vfat signature on /dev/sda1.
Physical volume "/dev/sda1" successfully created
If lvmlockd is running, lvmetad is configured (use_lvmetad=1),
but lvmetad is not running, then commands will seg fault
when trying to send a message to lvmetad.
The difference is lvmetad being "active", not just "used".
We already have pv_count to report number of PVs that a VG has based
on metadata.
This patch exposes the information about how many of these PVs are
missing which is also useful information for a VG. Wwe could count
the sum of pv_missing reporting fields for each PV in the VG before,
but the new field is practical when reporting VG as a whole and there's
no need to process each PV from VG alone.
If 'vgcreate --shared' finds both sanlock and dlm are running,
print a more accurate error message:
"Found multiple lock managers, select one with --lock-type."
When neither is running, we still print:
"Failed to detect a running lock manager to select lock type."
Also, leave out the note about "circular buffer" which is
an internal imeplementation detail anyway and not quite
informational for users:
Before this patch:
$ vgcreate vg1 /dev/sda
VG vg1 metadata too large for circular buffer
Failed to write VG vg1.
With this patch applied:
$ vgcreate vg1 /dev/sda
VG vg1 metadata too large: size of metadata to write is 691 bytes while PV metadata area size on /dev/sda is 512 bytes.
Failed to write VG vg1.
Before this patch:
$ lvs -a -o name,layout,role test/lvmlock
LV Layout Role
[lvmlock] linear public
With this patch applied:
$ lvs -a -o name,layout,role test/lvmlock
LV Layout Role
[lvmlock] linear private,lockd,sanlock
Add metadata_devices and seg_metadata_le_ranges report fields.
Currently only defined for raid, but should probably be extended
to all other segment types that don't report all their device
usage in the 'devices' field.
When lvmetad_pvscan_vg() reads VG metadata from each PV,
it compares it to the last one to verify it matches.
If the VG metadata does not match on the PVs, an error
is printed and it fails to read the VG. In this error
case, use log_debug to show the differences between
the two unmatching copies of the metadata.
One host changes a VG, making the cached VG on another
host invalid. The other host then rereads the VG from
disk to get the latest copy. If the first host removed
a PV from the VG, the second host attempts to reread the
VG from old PV when rescanning. Reading the VG from the
removed PV fails, causing vg_read to return "VG not found".
The fix is to simply not fail when a VG is not found while
rereading a PV and continue without it.
(This doesn't happen if the second host happens to first
run a command like 'vgs' that triggers a global revalidation
of metadata.)
vgchange --lock-type iterates through LVs to ensure
no LVs are active before changing the lock type of
the VG, but the loop was not checking that an LV
actually has a lock before trying it, so it would
fail if the VG had any LVs that don't use locks,
e.g it would fail on a tmeta LV from a pool.
When using lvm shell, some structures which are cached in memory may be
reused. This happens for the struct label (a part of lvmcache_info
structure) when lvmetad is used in which case the PV scan is not
done that would normally overwrite these label structures in memory
and making them up-to-date.
This is all consequence of the fact that struct lvmcache_info and
struct label are not always assigned in the same part of the code.
For example, if lvmetad *is not* used, parts of the struct label are
reassigned in label_read fn while struct lvmcache_info is created
elsewhere. No part of the code reused struct label (and its "dev"
field) before calling label_read fn. That's why the real bug is
hidden when using lvm shell without lvmetad.
However, with lvmetad and lvm shell, the situation is a bit different.
The label_read fn is not called if lvmetad *is* used, hence the
struct label may have ended up not initialized properly.
There was missing assignment for the dev field in struct label
in _text_pv_write fn which caused this problem to appear in
lvm shell with lvmetad, for example:
Before this patch:
lvm> pvcreate /dev/sda
Physical volume "/dev/sda" successfully created
lvm> pvs /dev/sda
PV VG Fmt Attr PSize PFree
unknown device lvm2 --- 128.00m 128.00m
With this patch applied:
lvm> pvcreate /dev/sda
Physical volume "/dev/sda" successfully created
lvm> pvs /dev/sda
PV VG Fmt Attr PSize PFree
/dev/sda lvm2 --- 128.00m 128.00m
Also, this problem had not appeared before changes introduced
by commits e1a63905d1 through
3a6f91d713 which, among other
things, added proper label field type reporting. Before, label
reporting was the same as using struct physical_volume which
has its own dev field assigned and so this problem was not exposed.
When a command does a sequence of
vg_write + vg_commit + vg_write + vg_commit,
initialization of non-PV devices happens during the
first vg_write, and does not need to be repeated by
the second vg_write.
When creating a lockd VG, this sequence occurs because
the VG is first created, then the lockd data is created,
then the lockd data is then written to the VG metadata.
This applies the same rule/logic to dlm VGs that has always
existed for sanlock VGs. Allowing a dlm VG to be removed
while its lockspace was still running on other hosts largely
worked, but there were difficult problems if another VG with
the same name was recreated. Forcing the VG lockspace to
be stopped, gives both sanlock and dlm VGs the same behavior.
The code was expecting the wrong return value from
compare_config, which returns 0 when equal.
This is a problem for a lockd VG using multiple PVs
when the VG needs to be rescanned.
Certain stacks of cached LVs may have unexpected consequences.
So add a warning function called when LV is cached to detect
such caces and WARN user about them - the best we could do ATM.
When we insert layer we also move status flag-bits for certain LV types,
so internal volume_group structure remains consistent.
(Perhaps it's misuse of 'insert_layer' function and we should have
another similar function for this.)
Basically we aim to maintain the same state as after reading fresh
metadata out of volume group.
Currently we when i.e. cache 'raid' LV - this should transfer 'raidLV' flag
to _corigin LV and cache is no longer a raid.
TODO: bits for stacked devices needs more exact rules.
Add a new arg to lockd_start_vg() that indicates
it is being called for a new lockd VG, so that
lvmlockd knows the lockspace being started is new.
(Will be used by a following commit.)
Ensure make clean cleans any left-over file from their previous
location so they are not in conflict with new ones.
Also hide error message when .commands file is not present.
The regex filter (controlled by devices/filter lvm.conf setting) was
evaluated as the very last filter. However, this is not optimal when
it comes to restricting disk access - users define devices/filter
as well as devices/global_filter to avoid this.
The devices/global_filter is already positioned at the beginning of the
filter chain. We need to do the same for devices/filter.
Filter chains before this patch:
A: when lvmetad is not used:
persistent_filter -> sysfs_filter -> global_regex_filter ->
type_filter -> usable->filter -> mpath_component_filter ->
partition_filter -> md_component_filter -> fw_raid_filter ->
regex_filter
B: when lvmetad is used:
B1: to update lvmetad:
sysfs_filter -> global_regex_filter -> type_filter ->
usable_filter -> mpath_component_filter -> partition_filter ->
md_component_filter -> fw_raid_filter
B2: to retrieve info from lvmetad:
persistent_filter -> usable_filter -> regex_filter
From the chain list above we can see that particularly in case when
lvmetad is not used, the regex filter is the very last one that is
processed. If lvmetad is used, it doesn't matter much as there's
the global_regex_filter which is used instead when updating lvmetad
and when retrieving info from lvmetad, putting regex_filter in front
of usable_filter wouldn't change much since usabled_filter is not
reading disks directly.
This patch puts the regex filter to the front even in case lvmetad
is not used, hence reinstating the state as it was before commit
a7be3b12df (which moved the regex_filter
position in the chain). Still, the arguments for the commit
a7be3b12df still apply and they're
still satisfied since component filters (MD, mpath...) are evaluated
first just before updating lvmetad.
So with this patch, we end up with:
A: when lvmetad is not used:
persistent_filter -> sysfs_filter -> global_regex_filter ->
regex_filter -> type_filter -> usable->filter ->
mpath_component_filter -> partition_filter ->
md_component_filter -> fw_raid_filter
B: when lvmetad is used:
B1: to update lvmetad:
sysfs_filter -> global_regex_filter -> type_filter ->
usable_filter -> mpath_component_filter -> partition_filter ->
md_component_filter -> fw_raid_filter
B2: to retrieve info from lvmetad:
persistent_filter -> regex_filter -> usable_filter
This way, specifying the regex_filter in non-lvmetad case causes
the devices to be filtered based on regex first before processing
any other filters which can access disks (like md_component_filter).
This patch also streamlines the code for better readability.
Relocate generated configure.h and lvm-version.h outside
of compilable .c source tree.
The reason is behind - when compiling in builddir != srcdir
the generated file in lib/misc/configure.h was used for all compiled
source file except ones located in lib/misc dir - those would have used
configure.h file located in this dir - if there have existed one (i.e.
from some other build)
This problem was only visible, when srcdir == buildir was used before
trying to use srcdri != builddir (as configure.h appeared then in
srcdir).
As part of fix that came with cf700151eb,
I forgot to add the check whether the result of stat was successful or
not. This bug caused uninitialized buffer to be used for entries
from .cache file which are no longer valid.
This bug may have caused these uninitialized values to be used further,
for example (see the unreal (2567,590944) representing major:minor
pair):
$ pvs
/dev/abc: stat failed: No such file or directory
Path /dev/abc no longer valid for device(2567,590944)
PV VG Fmt Attr PSize PFree
/dev/mapper/test lvm2 --- 104.00m 104.00m
/dev/vda2 rhel lvm2 a-- 9.51g 0
Since we may easily get blocked when checking for percentage
of thin-pool - do not flush and just show current values.
This avoids holding VG locked when pool is overfilled.
Try to detect thin-pool which my block lvm2 command from furher
processing (i.e. lvextend).
Check if pool is read-only or out-of-space and in this case thins
will skipped from being scanned (so user may miss some PVs located
on thin volumes).
Fix regression introduced with commit:
2fc126b00d
This commit has moved pv_min_size() test in front
of device_is_usable(). However pv_min_size needs to open device,
so it may have actually get blocked.
So restore the original order and first validate
dm device to be usable for open.
It's worth to note that such check is not 'race-free',
but it usually eliminates 99.99% of problems ;).
Print [source:handler] in filters' debug messages only if external
device info source other than "none" is used.
$ lvmconfig --type full devices/external_device_info_source
external_device_info_source="none
Before this patch (from the -vvvv log):
filters/filter-usable.c:47 /dev/mapper/test: Skipping: Too small to hold a PV [none:(nil)]
filters/filter-md.c:33 /dev/sdb: Skipping md component device [none:(nil)]
filters/filter-partitioned.c:25 /dev/vda: Skipping: Partition table signature found [none:(nil)]
With this patch applied:
filters/filter-usable.c:44 /dev/mapper/test: Skipping: Too small to hold a PV
filters/filter-md.c:35 /dev/sdb: Skipping md component device
filters/filter-partitioned.c:27 /dev/vda: Skipping: Partition table signature found
This was only used to return two flags indicating specific
reasons for a lock failure so that a more specific error
message could be printed by the command (lockspace had been
stopped, or lockspace had an error starting.)
Remove the list, given its limited usefulness, the fact it
would easily become inaccurate, and the fact it was causing
misleading error messages. The error conditions it was meant
to help could be reported differently.
Previously, a command would only rescan a lockd VG
when lvmetad returned the "vg_invalid" flag indicating
that the cached copy was invalid (which is done by
lvmlockd.) This is still the only usual reason for
rescanning a lockd VG, but two new special cases are
added where we also do the rescan:
. When the --shared option is used to display lockd VGs
from hosts not using lvmlockd. This is the same case
as using --foreign to display foreign VGs, but --shared
was missing the corresponding bits to rescan the VGs.
. When a lockd VG is allowed to be read for displaying
after failing to acquire the lock from lvmlockd. In
this case, the usual mechanism for validating the
cache is missed, so assume the cache would have been
invalidated. (This had been a previous todo item
that was lost during other cleanup.)
These were long-standing todos that were lost track of.
This makes lvmlockd removal steps for dlm VGs closely match
sanlock VGs. Because dlm lockspaces are not required to be
stopped on all hosts before vgremove, there is an extra bit
for dlm lockspaces, where a flag is set in the VG lock lvb
indicating that the VG was removed. If other hosts happen
to use the VG lock they will see this flag and stop their
lockspace.
Remove the existing lock type using the same functions
used to remove the lockd components during vgremove.
This results in a "clean" VG and lvmlockd state after
the vgchange, i.e. no bits left over from previous
lock type.
Since cache-pool actualy keeps info about caching,
display this info for cache-pool LV as well
(matches info for cache LV when cache-pool is asociated with it).
Fix the version export macros to make it possible to export two
different DM_* versions of a symbol: currently it is only possible for a
DM_* symbol to override a symbol in Base. Attempting to export two
symbols at different DM_* version levels (e.g. DM_1_02_104 and
DM_1_02_106) leads to a linker error due to a duplicate symbol
definition.
This is because the DM_EXPORTED_SYMBOL macro makes each exported symbol
the default (@@VERSION):
__asm__(".symver " #func "_v" #ver ", " #func "@@DM_" #ver )
Fix the macro to use a single '@' for a symbols exported in multiple
versions and rename the macros to DM_EXPORT_*:
DM_EXPORT_SYMBOL(func,ver)
DM_EXPORT_SYMBOL_BASE(func,ver)
For functions that have multiple implementations these macros control
symbol export and versioning.
Function definitions that exist in only one version never need to use
these macros.
Backwards compatible implementations must include a version tag of
the form "_v1_02_104" as a suffix to the function name and use the
macro DM_EXPORT_SYMBOL to export the function and bind it to the
specified version string.
Since versioning is only available when compiling with GCC the entire
compatibility version should be enclosed in '#if defined(__GNUC__)',
for example:
int dm_foo(int bar)
{
return bar;
}
#if defined(__GNUC__)
// Backward compatible dm_foo() version 1.02.104
int dm_foo_v1_02_104(void);
int dm_foo_v1_02_104(void)
{
return 0;
}
DM_EXPORT_SYMBOL(dm_foo,1_02_104)
#endif
A prototype for the compatibility version is required as these
functions must not be declared static.
The DM_EXPORT_SYMBOL_BASE macro is only used to export the base
versions of library symbols prior to the introduction of symbol
versioning: it must never be used for new symbols.
This mainly makes the description text use 80 columns.
There are a few minor adjustments to wording to help
the text layout, and a couple minor improvements to
descriptions.
This reverts commit 70db1d523d.
Since we use 'strncpy' even for case where it exactly matches
the buffer size and \0 is not expected to be added there.
Before printing a commented automatic config value,
print a line describing what it is. Otherwise, the
commented value can look like it's a part of an
example preceding it.
Move code which runtime detects settings for cache_policy
out of config dir to cache seg handling code.
Also mark cache_mode as command profilable setting.
Revert back to already existing behavior which has been slightly
modified by a900d150e4.
At the end however it seem to be equal to change TID right with first
metadata write.
Existing code missed handling for 'unused' thin-pool which would
require to also check empty message list for TID==0.
So with the fix we now again preserve 'active' thin-pool volume
when first thin volume is created - this property was lost and caused
problems in cluster, where the lock was hold, but volume was no longer
active on the node.
Another missing part was the proper support for already increased,
but unfinished TID change.
So going back here with existing logic -
TID is increased with first MDA update.
Code allows start with either same TID or (TID-1).
If there are messages, TID must be lower by 1 for sending,
otherwise messages were already posted.
As cache_policy is evaluated in runtime, we no longer should use
CFG_COMMENTED, but have to switch to CFG_UNDEFINED.
So as long as the value is undefined, it's runtime evaluated.
Once it's set - it's always respected (no runtime fallback).
Also fix version of introduced settings to 2.2.128.
If the Linux timerfd interface to POSIX timers is available at compile
time use it for all report interval timekeeping. This gives more
accurate interval timing when the per-interval processing time is less
than the configured interval and simplifies the timestamp bookkeeping
required to keep accurate time.
For systems without timerfd support fall back to the simple usleep based
timer.
