Re: [PERFORM] to fsync or not to fsync

2004-07-06 Thread Frank Hsueh
Rodrigo,

 Hello there, I'm trying to make sure my postgres 7.4 is running as fast
 as it can in my box.

 ...

 My Software config is:
 
 RedHat 7.3 - 2.4.20-28.7smp Kernel, reporting four processors because of
 hyper threading.
 Postgres 7.4
 Data directory is on a ext3 journaled filesystem (data=journal)

Isn't ext3 a really slow journaled filesystem [1, 2] to begin with?

[1] http://slashdot.org/article.pl?sid=04/05/11/134214
[2] http://209.81.41.149/~jpiszcz/index.html

It might be a good experiment to figure out how different file systems
affect perf.

-- 
Frank Hsueh, EngSci Elec 0T3 + 1

email: [EMAIL PROTECTED]

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Re: [PERFORM] to fsync or not to fsync (ext3?)

2004-07-06 Thread Rodrigo Filgueira
Frank, thanks for your answer,
This article http://www.linuxjournal.com/print.php?sid=5841 evaluates 
performance from a relational database point of view and it concludes 
that ext3 is faster.
The articles you provided evaluate filesystems by using basic shell 
commands, copy, tar, touch.
I really don't know why ext3 would be faster for databases but here are 
some tests that suggest this is true,

I run pgbench with data=writeback for ext3, this is as ext2 as an ext3 
fs can get, and results are more or less the same as with data=journal

Best run with data=journal

[EMAIL PROTECTED] pgbench]# ./pgbench -U dba -P 4ghinec osdb -c 10 -s 11 -t 1000
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 10
number of transactions per client: 1000
number of transactions actually processed: 1/1
tps = 349.844978 (including connections establishing)
tps = 350.715286 (excluding connections establishing)
Best run with data=writeback

[EMAIL PROTECTED] pgbench]# ./pgbench -U dba -P 4ghinec osdb -c 10 -s 11 -t 1000
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 10
number of transactions per client: 1000
number of transactions actually processed: 1/1
tps = 319.239210 (including connections establishing)
tps = 319.961564 (excluding connections establishing)
anybody else can throw some light on this?
Frank Hsueh wrote:
Rodrigo,
 

Hello there, I'm trying to make sure my postgres 7.4 is running as fast
as it can in my box.
   

My Software config is:
RedHat 7.3 - 2.4.20-28.7smp Kernel, reporting four processors because of
hyper threading.
Postgres 7.4
Data directory is on a ext3 journaled filesystem (data=journal)
   

Isn't ext3 a really slow journaled filesystem [1, 2] to begin with?
[1] http://slashdot.org/article.pl?sid=04/05/11/134214
[2] http://209.81.41.149/~jpiszcz/index.html
It might be a good experiment to figure out how different file systems
affect perf.
 

Rodrigo Filgueira Prates
[EMAIL PROTECTED]/OIT
http://www.cinterfor.org.uy

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