Details
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Type:
Bug
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Status: Open (View Workflow)
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Priority:
Critical
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Resolution: Unresolved
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Affects Version/s: 10.5.5
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Fix Version/s: None
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Component/s: Locking, Query Cache
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Labels:None
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Environment:mariadb 10.5.5-1
archlinux 5.7.12-arch1-1
query_cache_type = 1
query_cache_size = 64M
Description
ever since upgrading to 10.5 (from 10.4.14) we experience strange hangs of the mariadb server. This is a nice example:
818 | xx | localhost | xxx-2_1-unittest | Query | 14945 | closing tables | DROP DATABASE IF EXISTS `xxx-2_1-20200821055757` | 0.000 |
2002 | xxx | localhost | xxx-1_3-20200821055909 | Killed | 14879 | Waiting for query cache lock | INSERT INTO xxx | 0.000 |
2030 | root | localhost | Â | Query | 0 | starting | show processlist | 0.000 |
there seems to be no real relation between the DROP and the INSERT as they operate on completely different databases (they have no relation). I also have examples where there are multiple (killed) Waiting for query cache lock threads and a single DROP closing tables
The mariadbd consumes 100% CPU but I'm not sure what it's doing. strace shows some futex calls