Why did you have to drop shared buffers to 500MB, instead of
something just below 2GB?
Hello All,
Have a strange issue that I can not solve.
I have a new server that has 1TB ram (not a typo). I have
been fighting with this evening to start up with a shared_buffer
setting over 2GB. When the memory allocation breaks 2GB, the
database won’t start. I’ve dropped it down to 500M to get the
database online. We’ve tried both SysV memory and mmap memory.
Any ideas on what is going on and how to resolve? I’m sure
I’m missing something obvious, but it is totally eluding me.
OS: Ubuntu 18.04
Memory: 1007GB
CPU: Intel(R) Xeon(R) CPU X7550 @ 2.00GHz (64
cores total)
Kernel Memory:
kernel.shmmax = 274877906944
kernel.shmall = 17179869184
Postgres Config:
name |
setting
autovacuum_max_workers | 3
autovacuum_work_mem | -1
effective_cache_size | 98992128
fsync |
on
full_page_writes | on
maintenance_work_mem | 2097152
shared_buffers | 64000
shared_memory_type | sysv
temp_buffers | 4096
wal_buffers | 2048
work_mem | 119990
If you need additional parameters, please ask
SysV Error:
Feb 25 01:55:16 appdb-server01.production.aweberint.com
postgres[34680]: FATAL: could not create shared memory
segment: Cannot allocate memory
DETAIL: Failed system call was shmget(key=2359323,
size=2063564800, 03600).
HINT: This error usually means that PostgreSQL's request
for a shared memory segment exceeded your kernel's SHMALL
parameter. You might need to reconfigure the kernel with
larger SHMALL.
Mmap Error:
FATAL: could not map anonymous shared memory: Cannot
allocate memory
HINT: This error usually means that PostgreSQL's request
for a shared memory segment exceeded available memory, swap
space, or huge pages. To reduce the request size (currently
1635737600 bytes), reduce PostgreSQL's shared memory usage,
perhaps by reducing shared_buffers or max_connections.
Thanks,
Chris Hoover
Senior DBA
AWeber.com
Cell: (803) 528-2269
