On Fri, Apr 14, 2017 at 1:12 PM, Moreno Andreo <moreno.and...@evolu-s.it> wrote:
> Hi all, > About 2 hours and half ago, suddenly (and on the late afternoon of the > Easter Friday), customers reported failing connections to our server, or > even very slow. > After a bit of checking (that also involved server reboot) I noticed > (using top) that every process regarding postgres is using exactly the > amout I configured as work_mem (3 GB). And AFAIK it's not good. > > 30085 postgres 20 0 *3370048* 156656 153876 S 6.7 0.3 0:00.20 postgres > 29833 postgres 20 0 *3370000* 65260 62416 S 1.7 0.1 0:00.17 postgres > 29632 postgres 20 0 *3372468* 11712 6028 S 0.7 0.0 0:00.60 postgres > > What can be happened? > Nothing has been touched.... > postgresql 9.5.6 on debian 8 just apt-get upgrade'd > > Any help would be appreciated. > Moreno. > *>using exactly the amout I configured as work_mem (3 GB).* *You are right, that is bad, but that is your own fault. 3GB of work_mem is very bad, Try lowing in to something more reasonable, like 20GB.* *https://www.postgresql.org/docs/9.5/static/runtime-config-resource.html#RUNTIME-CONFIG-RESOURCE-MEMORY <https://www.postgresql.org/docs/9.5/static/runtime-config-resource.html#RUNTIME-CONFIG-RESOURCE-MEMORY>"several running sessions could be doing such operations concurrently. Therefore, the total memory used could be many times the value of work_mem; it is necessary to keep this fact in mind when choosing the value."* -- *Melvin Davidson* I reserve the right to fantasize. Whether or not you wish to share my fantasy is entirely up to you.
