 
> 1. Open WAL files with O_SYNC|O_DIRECT or O_SYNC(Not sure if 

Without grouping WAL writes that does not fly. Iff however such grouping
is implemented that should deliver optimal performance. I don't think flushing 
WAL to the OS early (before a tx commits) is necessary, since writing 8k or 256k 
to disk with one call takes nearly the same time. The WAL write would need to be 
done as soon as eighter 256k fill or a txn commits.

Andreas

Mon, 17 Nov 2003 12:15:00 +0100
"Zeugswetter Andreas SB SD" <ZeugswetterA@spardat.at>
Re: Background writer process
Zeugswetter Andreas SB SD wrote:
>>1. Open WAL files with O_SYNC|O_DIRECT or O_SYNC(Not sure if 
> Without grouping WAL writes that does not fly. Iff however such grouping
> is implemented that should deliver optimal performance. I don't think flushing 
> WAL to the OS early (before a tx commits) is necessary, since writing 8k or 256k 
> to disk with one call takes nearly the same time. The WAL write would need to be 
> done as soon as eighter 256k fill or a txn commits.

That means no special treatment to WAL files? If it works, great. There would be 
single class of files to take care w.r.t sync. issue. Even more simpler.

  Shridhar


Mon, 17 Nov 2003 17:28:29 +0530
Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
Re: Background writer process