database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-14 08:21:07 +03:00
Code Activity

Convert [autovacuum_]vacuum_cost_delay into floating-point GUCs.

Browse Source 
This change makes it possible to specify sub-millisecond delays,
which work well on most modern platforms, though that was not true
when the cost-delay feature was designed.

To support this without breaking existing configuration entries,
improve guc.c to allow floating-point GUCs to have units.  Also,
allow "us" (microseconds) as an input/output unit for time-unit GUCs.
(It's not allowed as a base unit, at least not yet.)

Likewise change the autovacuum_vacuum_cost_delay reloption to be
floating-point; this forces a catversion bump because the layout of
StdRdOptions changes.

This patch doesn't in itself change the default values or allowed
ranges for these parameters, and it should not affect the behavior
for any already-allowed setting for them.

Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
This commit is contained in:
Tom Lane
2019-03-10 15:01:39 -04:00
parent 28a65fc360
commit caf626b2cd
15 changed files with 242 additions and 157 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/backend/utils/misc/postgresql.conf.sample
View File

@ -155,7 +155,7 @@
# - Cost-Based Vacuum Delay -
#vacuum_cost_delay = 0 # 0-100 milliseconds
#vacuum_cost_delay = 0 # 0-100 milliseconds (0 disables)
#vacuum_cost_page_hit = 1 # 0-10000 credits
#vacuum_cost_page_miss = 10 # 0-10000 credits
#vacuum_cost_page_dirty = 20 # 0-10000 credits