Re: [BENCH MARK] 'tiobench' results comparision for 2.5.43 kernel and 2.4.19

From: Andrew Morton (
Date: Wed Oct 16 2002 - 11:37:33 EST

Siva Koti Reddy wrote:
> Hai...
> Here is the benchmark results of tiobench for 2.5.43 kernel and 2.4.19
> kernel. There is a drastic performance degradation in Read operations of
> 2.5.43 kernel as compared to 2.4.19 kernel though there is a little
> improvement in write operations. Any cooments..?

The tiobench threaded read phase is very sensitive to the
interworking between readahead and the disk scheduler. 2.4
gets this right, and 2.5 does not.

2.5 seeks between the files with a granularity equal to the
readahead window size. 2.4 seeks betwen the files at a
granularity equal to the elevator request expiry count.

So yup, it's known. Haven't investigated it yet.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

This archive was generated by hypermail 2b29 : Wed Oct 23 2002 - 22:00:29 EST