Symptoms
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Database dump fails with the following error:
# plesk db dump example_db > /var/www/vhosts/example.com/example.sql
signal: killed
mysqldump: Got errno 32 on write -
The following entries are found in
/var/log/messages
:test kernel: systemd invoked oom-killer: gfp_mask=0x201da, order=0, oom_score_adj=0
test kernel: systemd cpuset=/ mems_allowed=0test kernel: lowmem_reserve[]: 0 0 0 0
test kernel: Node 0 DMA: 3_4kB (M) 6_8kB (UEM) 7_16kB (UEM) 2_32kB (UM) 2_64kB (M) 1_128kB (E) 2_256kB (EM) 1_512kB (E) 2_1024kB (UE) 2_2048kB (EM) 0_4096kB = 7660kB
test kernel: Node 0 DMA32: 283_4kB (UEM) 734_8kB (UE) 550_16kB (UE) 297_32kB (UEM) 222_64kB (UEM) 22_128kB (EM) 1_256kB (M) 0_512kB 0_1024kB 1_2048kB (M) 0_4096kB = 44636kB
test kernel: Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
test kernel: 58470 total pagecache pages
test kernel: 0 pages in swap cache
test kernel: Swap cache stats: add 0, delete 0, find 0/0
test kernel: Free swap = 0kB
test kernel: Total swap = 0kB
test kernel: 524153 pages RAM -
Dumping the database with the native MySQL command is successful:
# MYSQL_PWD=cat /etc/psa/.psa.shadow mysqldump -uadmin example_db > /var/www/vhosts/example.com/example.sql
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Memory on the server might be somewhat limited, e.g:
# free -mh
total used free shared buff/cache available
Mem: 1.8G 734M 157M 235M 946M 696M
Swap: 0B 0B 0B
Cause
The 'plesk db' command uses more memory than a native MySQL dump command. As a result, the process is being killed by OOM killer.
Resolution
Apply one or more of the following solutions:
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Adjust OOM settings
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Increase RAM on the server
-
Use native mysqldump:
# MYSQL_PWD=cat /etc/psa/.psa.shadow mysqldump -uadmin example_db > /var/www/vhosts/example.com/example.sql