Bruce Momjian wrote:
Yes. If you were doing multiple WAL writes before transaction fsync,
you would be fsyncing every write, rather than doing two writes and
fsync'ing them both. I wonder if larger transactions would find
open_sync slower?
No hard numbers, but I remember testing fsync vs
On Tue, 14 Oct 2003, Tom Lane wrote:
scott.marlowe [EMAIL PROTECTED] writes:
open_sync was WAY faster at this than the other two methods.
Do you not have open_datasync? That's the preferred method if
available.
Nope, when I try to start postgresql with it set to that, I get this error
BM == Bruce Momjian [EMAIL PROTECTED] writes:
BM COPY only does fsync on COPY completion, so I am not sure there are
BM enough fsync's there to make a difference.
Perhaps then it is part of the indexing that takes so much time with
the WAL. When I applied Marc's WAL disabling patch, it shaved
On Thu, 9 Oct 2003, Bruce Momjian wrote:
scott.marlowe wrote:
I was testing to get some idea of how to speed up the speed of pgbench
with IDE drives and the write caching turned off in Linux (i.e. hdparm -W0
/dev/hdx).
The only parameter that seems to make a noticeable difference
scott.marlowe wrote:
On Thu, 9 Oct 2003, Bruce Momjian wrote:
scott.marlowe wrote:
I was testing to get some idea of how to speed up the speed of pgbench
with IDE drives and the write caching turned off in Linux (i.e. hdparm -W0
/dev/hdx).
The only parameter that seems to
On Fri, 10 Oct 2003, Josh Berkus wrote:
Bruce,
Yes. If you were doing multiple WAL writes before transaction fsync,
you would be fsyncing every write, rather than doing two writes and
fsync'ing them both. I wonder if larger transactions would find
open_sync slower?
Want me to
Josh Berkus wrote:
Bruce,
Yes. If you were doing multiple WAL writes before transaction fsync,
you would be fsyncing every write, rather than doing two writes and
fsync'ing them both. I wonder if larger transactions would find
open_sync slower?
Want me to test? I've got an
Bruce,
I would be interested to see if wal_sync_method = fsync is slower than
wal_sync_method = open_sync. How often are we doing more then one write
before a fsync anyway?
OK. I'll see if I can get to it around my other stuff I have to do this
weekend.
--
Josh Berkus
Aglio Database
BM == Bruce Momjian [EMAIL PROTECTED] writes:
Sounds reasonable to me. Are there many / any scenarios where a plain
fsync would be faster than open_sync?
BM Yes. If you were doing multiple WAL writes before transaction fsync,
BM you would be fsyncing every write, rather than doing two
Vivek Khera wrote:
BM == Bruce Momjian [EMAIL PROTECTED] writes:
Sounds reasonable to me. Are there many / any scenarios where a plain
fsync would be faster than open_sync?
BM Yes. If you were doing multiple WAL writes before transaction fsync,
BM you would be fsyncing every write,
On Fri, 10 Oct 2003, Josh Berkus wrote:
Bruce,
Yes. If you were doing multiple WAL writes before transaction fsync,
you would be fsyncing every write, rather than doing two writes and
fsync'ing them both. I wonder if larger transactions would find
open_sync slower?
Want me to
How did this drive come by default? Write-cache disabled?
---
scott.marlowe wrote:
On Thu, 2 Oct 2003, scott.marlowe wrote:
I was testing to get some idea of how to speed up the speed of pgbench
with IDE drives and
12 matches
Mail list logo
