I have issue that update queries is slow, I need some advice how improve
speed. I don't have much control to change queries. But I can change
postresql server configuration
query example:
UPDATE "project_work" SET "left" = ("project_work"."left" + 2) WHERE
("project_work"."left" >= 8366)
sometimes updated lines count is up to 10k
postgresql version 9.3
postgresl.conf
max_connections = 100
shared_buffers = 6GB # min 128kB
work_mem = 100MB # min 64kB
all other values are default
server hardware
Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz
16GB RAM
disk is HDD
about half of resource I can dedicate for postgresql server.