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| author | Marko Mäkelä <marko.makela@mariadb.com> | 2020-10-27 15:35:04 +0200 |
|---|---|---|
| committer | Marko Mäkelä <marko.makela@mariadb.com> | 2020-10-27 15:47:18 +0200 |
| commit | 42e1815ad850384fad292534665ff61b78dd96f6 (patch) | |
| tree | 88e1dbc62723abf652911cd73838c0e8797dae01 /storage | |
| parent | 8761571a71f0d628c5a82abed115e170d63e34c0 (diff) | |
| download | mariadb-git-42e1815ad850384fad292534665ff61b78dd96f6.tar.gz | |
MDEV-16952 Introduce SET GLOBAL innodb_max_purge_lag_wait
Let us introduce a dummy variable innodb_max_purge_lag_wait
for waiting that the InnoDB history list length is below
the user-specified limit. Specifically,
SET GLOBAL innodb_max_purge_lag_wait=0;
should wait for all history to be purged. This could be useful
when upgrading from an older version to MariaDB 10.3 or later,
to avoid hitting MDEV-15912.
Note: the history cannot be purged if there exist transactions
that may see old versions.
Reviewed by: Vladislav Vaintroub
Diffstat (limited to 'storage')
| -rw-r--r-- | storage/innobase/handler/ha_innodb.cc | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc index e36dcbad8ff..3db462ee92d 100644 --- a/storage/innobase/handler/ha_innodb.cc +++ b/storage/innobase/handler/ha_innodb.cc @@ -271,6 +271,27 @@ enum default_row_format_enum { DEFAULT_ROW_FORMAT_DYNAMIC = 2, }; +/** A dummy variable */ +static uint innodb_max_purge_lag_wait; + +/** Wait for trx_sys_t::rseg_history_len to be below a limit. */ +static void innodb_max_purge_lag_wait_update(THD *thd, st_mysql_sys_var *, + void *, const void *limit) +{ + const uint l= *static_cast<const uint*>(limit); + if (trx_sys->rseg_history_len <= l) + return; + mysql_mutex_unlock(&LOCK_global_system_variables); + while (trx_sys->rseg_history_len > l) + { + if (thd_kill_level(thd)) + break; + srv_wake_purge_thread_if_not_active(); + os_thread_sleep(100000); + } + mysql_mutex_lock(&LOCK_global_system_variables); +} + static void set_my_errno(int err) { @@ -20147,6 +20168,11 @@ static MYSQL_SYSVAR_ULONG(max_purge_lag_delay, srv_max_purge_lag_delay, 0L, /* Minimum value */ 10000000UL, 0); /* Maximum value */ +static MYSQL_SYSVAR_UINT(max_purge_lag_wait, innodb_max_purge_lag_wait, + PLUGIN_VAR_RQCMDARG, + "Wait until History list length is below the specified limit", + NULL, innodb_max_purge_lag_wait_update, UINT_MAX, 0, UINT_MAX, 0); + static MYSQL_SYSVAR_BOOL(rollback_on_timeout, innobase_rollback_on_timeout, PLUGIN_VAR_OPCMDARG | PLUGIN_VAR_READONLY, "Roll back the complete transaction on lock wait timeout, for 4.x compatibility (disabled by default)", @@ -21195,6 +21221,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= { MYSQL_SYSVAR(flushing_avg_loops), MYSQL_SYSVAR(max_purge_lag), MYSQL_SYSVAR(max_purge_lag_delay), + MYSQL_SYSVAR(max_purge_lag_wait), MYSQL_SYSVAR(old_blocks_pct), MYSQL_SYSVAR(old_blocks_time), MYSQL_SYSVAR(open_files), |