I've ran out of ideas

Luke lukem at cse.unsw.EDU.AU
Thu Nov 18 19:16:56 PST 2004

On Thu, 18 Nov 2004, Aaron Glenn wrote:
>> I would theorise that your web server is probably only issuing fairly
>> small disk reads, so your network performance is being bound by the disk.
> That was my first hunch; hence creating a separate partition with
> obscene blocksizes (-:

Increasing the block size of the disk need not imply that the application 
is issuing larger reads.

>> To test this theory, you could:
>> * create an mfs partition and serve off it to see what kind of performance
>>    you can get
>> * see if you can tweak the web server to use larger reads and writes.
>> In your original message you said that increasing the disk block size
>> improved performance, which would also indicate that you are being limited
>> by disk performance.
> I doubt increasing it even more would help. Law of diminishing returns
> and all that; then again I'm no expert. Thoughts?

I have not suggested that you increase the blocksize further. Please read 
the above points again.

As Sean pointed out, if your web server supports sendfile then that would 
be a good option.

Your recent post which showed poor performance from /dev/zero does bring 
the theory that your disk is the bottleneck into question, however you may 
still find it is worth trying the above suggestions.


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