Re: Drastic Slowdown of 'fseek()' Calls From 2.4 to 2.6 -- VMM Change?

From: Robert Hancock
Date: Fri Feb 24 2006 - 18:30:04 EST


Marr wrote:
Clearly, the 2.4.31 results are speedy because the whole 4MB file has been cached.

I don't think this is clear at all. The entire file should always be cached, not doing this would be insane.

What I cannot figure out is this: what has changed in 2.6.x kernels to cause the performance to degrade so drastically?!?

fseek() is a C library call, not a system call itself - there may be something that glibc is doing differently. Are you using the same glibc version with both kernels?

Just from this program it could be something else entirely that explains the difference in speed, like the random number generator..

--
Robert Hancock Saskatoon, SK, Canada
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Home Page: http://www.roberthancock.com/

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