Curioser and Curiouser

  • From: Niall Litchfield <niall.litchfield@xxxxxxxxx>
  • To: "oracle-l@xxxxxxxxxxxxx" <oracle-l@xxxxxxxxxxxxx>
  • Date: Wed, 12 Jan 2005 14:46:35 +0000

I'm - not for the first time bemused - I wonder if anyone can (after
fighting past the screwed up formatting that blogger gave me) shed
light on the results that I have on my site for running identical SQL
on identical hardware (the same machine actually) under Windows XP sp2
and Fedora Core 3 linux. (incidentally FC3 passed the certified os
checks on install).

briefly the test is

create a table with 20k rows. 
insert into the table all the rows from itself 6 times

tune based on the response time (I've used tkprof to generate the
response time profile).

My linux box seems to be stuck waiting on log_buffer space and whilst
throwing memory at it has helped (I've gone as high as 8mb log buffer
and to my surprise got some marginal improvement over the 1mb I've
documented) it is still half the speed of the same hardware running
windows. some mistake surely.

My kernel parameters are

kernel.shmall = 2097152
kernel.shmmax = 2147483648
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000

because I followed John Smiley's article for the install


Niall Litchfield
Oracle DBA

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