Hi Community,
I'm asking for your lights because i'm having memory problems with postgres.
Examples of logs :
FATAL: could not fork new process for connection: Cannot allocate memory could not fork new process for connection: Cannot allocate memory
out of memory DETAIL: Failed on request of size 32800 in memory context "HashBatchContext".
out of memory DETAIL Failed on request of size 288 in memory context "CacheMemoryContext".
We use postgresql (primary/standby) with pgbouncer as a pooler, and repmgr as replication manager.
We have ~ 2000 connections at the same time with ~ 20/30 are active. (we need to set a high number of connexion on postgres, because our app uses a lot of different users, and each user on each app server needs multiple and constant connexions).
Here is my configuration :
system :
Debian : 9.13
Memory : 380 Go
Postgres : 12.4-1.pgdg90+1
Pgbouncer : 1.14
kernel.shmmax = 202591600640
kernel.shmall = 49460840
postgres :
dynamic_shared_memory_type = posix # the default is the first option
max_connections = 2600 # (change requires restart)
work_mem = 96MB # min 64kB
maintenance_work_mem = 8GB # min 1MB
shared_buffers = 64GB # min 128kB
temp_buffers = 32MB # min 800kB
wal_buffers = 16MB # min 32kB, -1 sets based on shared_buffers
effective_cache_size = 270GB
pgbouncer :
max_client_conn = 6000
default_pool_size = 2590
reserve_pool_size = 5
pool_mode = session
Do you think that our parameters are not correct compared to our configuration? Do you have an idea ?
Best regards.
Michael.