Re: Another WAL question - Mailing list pgsql-admin

From Bruce Momjian
Subject Re: Another WAL question
Date
Msg-id 200109121732.f8CHWVp18785@candle.pha.pa.us
Whole thread Raw
In response to Another WAL question  ("Nick Fankhauser" <nickf@ontko.com>)
Responses Re: Another WAL question
List pgsql-admin
In 7.1.3 and 7.2, there are only 2-3 WAL files kept because there is no
need to keep them after a checkpoint.  Is there any need to have these
WAL config paramaters anymore?

We currently have in postgresql.conf:

#wal_buffers = 8            # min 4
#wal_files = 0 # range 0-64
#wal_sync_method = fsync   # fsync or fdatasync or open_sync or
open_datasync
# Note: default wal_sync_method varies across platforms
#wal_debug = 0             # range 0-16
#commit_delay = 0          # range 0-100000
#commit_siblings = 5       # range 1-1000
#checkpoint_segments = 3   # in logfile segments (16MB each), min 1
#checkpoint_timeout = 300  # in seconds, range 30-3600


> Robert F. mentioned that there is a config parameter controlling the number
> of WAL files in postgresql.conf.
>
> I just looked at the Doc on this & I found WAL_FILES, which appears to
> specify the number of files to create in advance, but it is no clear to me
> that this limits the total number of WAL files created. Can this number be
> exceeded as needed by the postmaster? If so, is there another parameter that
> I'm missing to set a limit?
>
> Are old WAL files deleted or re-used automatically when all of their
> contents have been flushed to the DB, or should we be watching these &
> either archiving or deleting old ones?
>
> TIA,
>
> -Nick
>
> ---------------------------------------------------------------------
> Nick Fankhauser
>
> Business:
> nickf@doxpop.com  Phone 1.765.965.7363  Fax 1.765.962.9788
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>
> Personal:
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>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
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