From a47839f1fa123ddbcbfbeab1a7d3c89ddb2d016d Mon Sep 17 00:00:00 2001
From: Guillermo Ramos <gramos@opennebula.io>
Date: Tue, 8 Oct 2024 10:11:29 +0200
Subject: [PATCH] Optimize snapshots usage in RBD incr. restore
- Incremental backups only keep the last snapshot, to be used as base in
the next one.
- Restore operation deletes the previous snapshots, because at that
point the chain is reset and they're no longer going to be used.
- Starting a new FULL backup also deletes previous inc snapshots.
- Refactor the remote execution logic to make it more composable.
Signed-off-by: Guillermo Ramos <gramos@opennebula.io>
(cherry picked from commit 1790b5f3f9ac55e3149f5344580330c27d5585df)
(cherry picked from commit 7ddf9b3b72801f5528c39e0923ca58941498fd22)
---
src/tm_mad/lib/ceph.rb | 70 +++++++++++++++++++++++++++++++++---------
1 file changed, 55 insertions(+), 15 deletions(-)
diff --git a/src/tm_mad/lib/ceph.rb b/src/tm_mad/lib/ceph.rb
index 17472591e0..f5876cf4da 100644
--- a/src/tm_mad/lib/ceph.rb
+++ b/src/tm_mad/lib/ceph.rb
@@ -91,6 +91,9 @@ module TransferManager
# Ceph disks
class Disk
+ # DON'T CHANGE THIS CONSTANT; will break existing incremental backups
+ INC_SNAP_PREFIX = 'one_backup_'
+
attr_reader :id, :vmid, :source, :clone, :rbd_image, :rbd_cmd
# @param vm_xml [String, REXML::Element]
@@ -146,6 +149,28 @@ module TransferManager
['fs', 'swap'].include?(@type)
end
+ # @param filter [nil, {type: [:prefix, :eq], text: String}]
+ def rm_snaps_sh(filter = nil, image = @rbd_image)
+ jqfilter =
+ if filter.nil?
+ nil
+ elsif filter[:type] == :prefix
+ ".name | startswith(\"#{filter[:text]}\")"
+ elsif filter[:type] == :eq
+ ".name == \"#{filter[:text]}\""
+ end
+ rmfilter = "| select(#{jqfilter})" if jqfilter
+
+ <<~EOF
+ #{@rbd_cmd} snap ls #{image} --format json | \
+ jq -r '.[] #{rmfilter} .name' | \
+ xargs -rn1 sh -c ' \
+ #{@rbd_cmd} snap unprotect #{image}@$1 > /dev/null 2>&1 || true; \
+ #{@rbd_cmd} snap rm #{image}@$1; \
+ ' sh
+ EOF
+ end
+
# @param backup_dir [String]
# @param ds [TransferManager::Datastore]
# @param live [Boolean]
@@ -182,21 +207,19 @@ module TransferManager
)
clup_cmd << "rm -f #{draw}\n"
+
+ # Remove old incremental snapshots after starting a full one
+ clup_cmd << rm_snaps_sh({ :type => :prefix, :text => INC_SNAP_PREFIX })
+
elsif @vm_backup_config[:last_increment] == -1
# First incremental backup (similar to full but snapshot must be preserved)
incid = 0
dexp = "#{backup_dir}/disk.#{@id}.rbd2"
- sprefix = 'one_backup_'
- snapshot = "#{@rbd_image}@#{sprefix}#{incid}"
+ snapshot = "#{@rbd_image}@#{INC_SNAP_PREFIX}#{incid}"
snap_cmd << <<~EOF
- #{@rbd_cmd} snap ls #{@rbd_image} --format json | \
- jq -r '.[] | select(.protected == "true" and (.name | startswith("#{sprefix}"))).name' | \
- xargs -rI{} #{@rbd_cmd} snap unprotect #{@rbd_image}@{}
- #{@rbd_cmd} snap ls #{@rbd_image} --format json | \
- jq -r '.[] | select(.name | startswith("#{sprefix}")).name' | \
- xargs -rI{} #{@rbd_cmd} snap rm #{@rbd_image}@{}
+ #{rm_snaps_sh({ :type => :prefix, :text => INC_SNAP_PREFIX })}
#{@rbd_cmd} snap create #{snapshot}
#{@rbd_cmd} snap protect #{snapshot}
EOF
@@ -221,6 +244,9 @@ module TransferManager
"#{@rbd_cmd} export-diff --from-snap #{last_snap} #{snapshot} #{dinc}\n",
backup_dir
)
+
+ old_snapshot = "one_backup_#{@vm_backup_config[:last_increment]}"
+ clup_cmd << rm_snaps_sh({ :type => :eq, :text => old_snapshot })
end
{
@@ -231,20 +257,17 @@ module TransferManager
end
def restore_sh(target, bridge = nil)
- ssh = bridge ? "ssh #{bridge}" : ''
<<~EOF
# Upload base image and snapshot
- #{ssh} #{@rbd_cmd} import --export-format 2 - #{target} < disk.*.rbd2
+ #{Disk.sshwrap(bridge, "#{@rbd_cmd} import --export-format 2 - #{target}")} < disk.*.rbd2
# Apply increments
for f in $(ls disk.*.*.rbdiff | sort -k3 -t.); do
- #{ssh} #{@rbd_cmd} import-diff - #{target} < $f
+ #{Disk.sshwrap(bridge, "#{@rbd_cmd} import-diff - #{target}")} < $f
done
- # Protect all snapshots
- #{ssh} #{@rbd_cmd} snap ls #{target} --format json | \
- jq -r '.[] | select(.protected == "false").name' | \
- xargs -I{} #{@rbd_cmd} snap protect #{target}@{}
+ # Delete snapshots
+ #{Disk.sshwrap(bridge, rm_snaps_sh({ :type => :prefix, :text => INC_SNAP_PREFIX }, target))}
EOF
end
@@ -294,6 +317,23 @@ module TransferManager
indexed_disks
end
+ # TODO: move to Shell.rb (f-5853)
+ def self.sshwrap(host, cmd)
+ cmd << "\n"
+ if host.nil?
+ cmd
+ else
+ <<~EOF.strip
+ ssh '#{host}' '\
+ script="$(mktemp)"; \
+ echo "#{Base64.strict_encode64(cmd)}" | base64 -d > "$script"; \
+ trap "rm $script" EXIT; \
+ bash "$script"; \
+ '
+ EOF
+ end
+ end
+
end
def self.xml_opt(disk_xml, name, opt)