Increase st_blksize to 64k

Christopher Faylor
Wed Jan 3 15:40:00 GMT 2007

On Wed, Jan 03, 2007 at 02:35:57PM +0100, Corinna Vinschen wrote:
>On Jan  3 06:20, Eric Blake wrote:
>> Hash: SHA1
>> According to Corinna Vinschen on 1/3/2007 5:16 AM:
>> > 
>> > Setting st_blksize to 64K might be a good idea for disk I/O if the value
>> > is actually used by applications.  Do you have a specific example or a
>> > test result from a Cygwin application which shows the advantage of
>> > setting st_blksize to this value?  I assume there was some actual case
>> > which led you to make this change ;)
>> Did you read the original link?
>Urgh, sorry, no.  I missed it even twice, once when scanning the Cygwin
>list to see what happened since Christmas, and once in Brian's mail
>starting this thread.
>So it appears to make much sense to set the blocksize to 64K.  The
>only question would be whether to use getpagesize() or a hard coded
>value.  It seems to me that the 64K allocation granularity and using
>64K as buffer size in disk I/O coincide so I tend to agree that it
>makes sort of sense to use getpagesize at this point.  What do you
>think, Chris?

I don't think getpagesize should be linked to this value.  The fact that
both are 64K seems to be a coincidence to me.  This wasn't mentioned in
the document that Brian mentioned was it?

If we specifically want to use 64K block sizes then I think we should
specifically say that rather than relying on some other unrelated mechanism
to return a 64K constant.


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