Stephen wrote:

Good news,

I partially fixed the problem on Linux 2.4. It appears the responsiveness
can be improved significantly by tuning the disk IO elevator in Linux using
"elvtune" in util-linux. The elevator in Linux is used to re-order
read/write requests to reduce disk seeks by ordering requests according to
disk sectors. Unfortunately, the elevator in kernel 2.4 is not very smart
(or flexible I should say depending on your needs) and can starve a
read/write request for a long time if not properly tuned.
elvtune -r 2048 -w 8192 /dev/hdc (default Redhat 9):
====================================================

Are you sure ? In my RH9.0 installation I obtain:


# elvtune /dev/sda7

/dev/sda7 elevator ID           5
        read_latency:           64
        write_latency:          8192
        max_bomb_segments:      6


may be your problem is due the fact that someone change these values on your machine!



Regards
Gaetano Mendola


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