------_=_NextPart_000_01C14C65.E377EB30
Content-Type: text/plain;
charset="utf-8"
We expierenced a panic when starting Oracle 8i with your patch(actually ac4)
right after the database was mounted. I will forward you the oops I posted
earlier today.
-----Original Message-----
From: Bond, Andrew
Sent: Wed 10/3/2001 4:47 PM
To: linux-kernel@vger.kernel.org
Cc: Nikolaiev, Mike; Jamshed Patel (E-mail)
Subject: [PATCH] kiobuf_init optimization
I have come up with a change to the kiobuf_init() routine that
drops the blind memset() to 0 of the entire kiobuf structure and zeros
out 3 specific fields instead. Since this is done on every IO and the
kiobuf structure is over 8K in size (8756 bytes I believe) it becomes
quite costly from a cpu cycle perspective as well as a cache utilization
perspective. The typical IO path uses a small subset of the
preallocated fields within the kiobuf structure. Therefore, the IO path
pays a performance penalty for having to zero out many fields that it
typically doesn't use.
The kiobuf_init() routine using a memset() of the entire kiobuf
structure is in the top 10 of cpu consuming kernel routines in Oracle 9i
testing using raw io. Using the included kiobuf_init patch, our testing
has shown a 5% improvement in Oracle transactional performance in 4 and
8 processor configurations, and the kiobuf_init() routine became a
non-issue for performance. The testing was performed with Oracle, but
this patch could provide performance improvements to any application
that uses raw IO or relies on kiobufs in the IO path.
Obviously, since the structure is no longer set to zero, any
code that makes a zero assumption would break. I haven't come across
code that makes this assumption yet for fields that I did not
specifically zero out in the patch, but I could very well be missing
something. It appears that Alan has included this patch in his
2.4.10-ac4 tree. So, let me know if you have any problems that you
think might be related to this patch. Any input would be greatly
appreciated.
The patch is against a 2.4.9 tree, but it is localized to just
the kiobuf_init() routine and should apply to any of the recent kernels.
Run from the root level of your kernel tree:
patch -p1 < kiobuf_init_speedup.patch
I cannot currently receive the kernel mailing list at this email
address, so please cc: me on posts related to this patch.
Thanks,
Andrew Bond
<<kiobuf_init_speedup.patch>>
------_=_NextPart_000_01C14C65.E377EB30
Content-Type: application/ms-tnef
Content-Transfer-Encoding: base64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------_=_NextPart_000_01C14C65.E377EB30--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/