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author | Daniel Baumann <mail@daniel-baumann.ch> | 2025-06-06 10:05:23 +0000 |
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committer | Daniel Baumann <mail@daniel-baumann.ch> | 2025-06-06 10:05:23 +0000 |
commit | 755cc582a2473d06f3a2131d506d0311cc70e9f9 (patch) | |
tree | 3efb1ddb8d57bbb4539ac0d229b384871c57820f /scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample | |
parent | Initial commit. (diff) | |
download | qemu-upstream.tar.xz qemu-upstream.zip |
Adding upstream version 1:7.2+dfsg.upstream/1%7.2+dfsgupstream
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
Diffstat (limited to 'scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample')
-rwxr-xr-x | scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample new file mode 100755 index 00000000..2b4fa3ae --- /dev/null +++ b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample @@ -0,0 +1,56 @@ +#!/bin/sh + +# Flush MySQL tables to the disk before the filesystem is frozen. +# At the same time, this keeps a read lock in order to avoid write accesses +# from the other clients until the filesystem is thawed. + +MYSQL="/usr/bin/mysql" +MYSQL_OPTS="-uroot" #"-prootpassword" +FIFO=/var/run/mysql-flush.fifo + +# Check mysql is installed and the server running +[ -x "$MYSQL" ] && "$MYSQL" $MYSQL_OPTS < /dev/null || exit 0 + +flush_and_wait() { + printf "FLUSH TABLES WITH READ LOCK \\G\n" + trap 'printf "$(date): $0 is killed\n">&2' HUP INT QUIT ALRM TERM + read < $FIFO + printf "UNLOCK TABLES \\G\n" + rm -f $FIFO +} + +case "$1" in + freeze) + mkfifo $FIFO || exit 1 + flush_and_wait | "$MYSQL" $MYSQL_OPTS & + # wait until every block is flushed + while [ "$(echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\ + "$MYSQL" $MYSQL_OPTS | tail -1 | cut -f 2)" -gt 0 ]; do + sleep 1 + done + # for InnoDB, wait until every log is flushed + INNODB_STATUS=$(mktemp /tmp/mysql-flush.XXXXXX) + [ $? -ne 0 ] && exit 2 + trap "rm -f $INNODB_STATUS; exit 1" HUP INT QUIT ALRM TERM + while :; do + printf "SHOW ENGINE INNODB STATUS \\G" |\ + "$MYSQL" $MYSQL_OPTS > $INNODB_STATUS + LOG_CURRENT=$(grep 'Log sequence number' $INNODB_STATUS |\ + tr -s ' ' | cut -d' ' -f4) + LOG_FLUSHED=$(grep 'Log flushed up to' $INNODB_STATUS |\ + tr -s ' ' | cut -d' ' -f5) + [ "$LOG_CURRENT" = "$LOG_FLUSHED" ] && break + sleep 1 + done + rm -f $INNODB_STATUS + ;; + + thaw) + [ ! -p $FIFO ] && exit 1 + echo > $FIFO + ;; + + *) + exit 1 + ;; +esac |