Hi
I add a new patch for zerocopy NFS.
va03-knfsd-zerocopy-sendpage-2.5.7-test1.patch makes knfsd to skip
csum_partial_copy_generic() which copies data into a sk_buff.
This feature works on when you use NFS over TCP only at this moment.
I'd like to implement sendpage for UDP, but it doesn't work yet.
But I wonder about sendpage. I guess HW IP checksum for outgoing
pages might be miscalculated as VFS can update them anytime.
New feature like COW pagecache should be added to VM and they
should be duplicated in this case.
Is there anyone who could advise me about this ?
Following patches patches are against linux 2.5.7
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va01-knfsd-zerocopy-vfsread-2.5.7.patch
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va02-kmap-multplepages-2.5.7.patch
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va03-knfsd-zerocopy-sendpage-2.5.7-test1.patch
Andrew, Could you try it again?
Regards,
Hirokazu Takahashi
_______________________________________________
NFS maillist - [email protected]
https://lists.sourceforge.net/lists/listinfo/nfs
> Hi
>
> I add a new patch for zerocopy NFS.
> va03-knfsd-zerocopy-sendpage-2.5.7-test1.patch makes knfsd to skip
> csum_partial_copy_generic() which copies data into a sk_buff.
> This feature works on when you use NFS over TCP only at this moment.
> I'd like to implement sendpage for UDP, but it doesn't work yet.
>
> But I wonder about sendpage. I guess HW IP checksum for outgoing
> pages might be miscalculated as VFS can update them anytime.
> New feature like COW pagecache should be added to VM and they
> should be duplicated in this case.
>
> Is there anyone who could advise me about this ?
>
>
> Following patches patches are against linux 2.5.7
>
>
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va01-knfsd-zerocopy-vfsre
ad-2.5.7.patch
>
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va02-kmap-multplepages-2.
5.7.patch
>
>
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va03-knfsd-zerocopy-sendp
age-2.5.7-test1.patch
>
>
> Andrew, Could you try it again?
Yes, thanks for the patch. My first attempt resulted in a system which
would not respond anymore. I did not have access to the console at the
time, so I am not sure why yet. If it happens again, I'll have some data to
go along with it. Once I get a working test, I should have some profiles
and throughput results.
Thanks again,
-Andrew
_______________________________________________
NFS maillist - [email protected]
https://lists.sourceforge.net/lists/listinfo/nfs
I tried the patch with great performance improvement! I ran my nfs read
test (48 clients read 200 MB file from one 4-way SMP NFS server) and
compared your patches to regular 2.5.7. Regular 2.5.7 resulted in 87 MB/sec
with 100% CPU utilization. Your patch resulted 130 MB/sec with 82% CPU
utilization! This is very good! I took profiles, and as expected,
csum_copy and file_read_actor were gone with the patch. Sar reported nearly
40 MB/sec per gigabit adapter (there are 4) during the test. That is the
most I have seen so far. Soon I will be doing some lock analysis to make
sure we don't have any locking problems. Also, I will see if there is
anyone here at IBM LTC that can assist with your development of zerocopy on
UDP. Thanks for the patch!
Andrew Theurer
> Hi
>
> I add a new patch for zerocopy NFS.
> va03-knfsd-zerocopy-sendpage-2.5.7-test1.patch makes knfsd to skip
> csum_partial_copy_generic() which copies data into a sk_buff.
> This feature works on when you use NFS over TCP only at this moment.
> I'd like to implement sendpage for UDP, but it doesn't work yet.
>
> But I wonder about sendpage. I guess HW IP checksum for outgoing
> pages might be miscalculated as VFS can update them anytime.
> New feature like COW pagecache should be added to VM and they
> should be duplicated in this case.
>
> Is there anyone who could advise me about this ?
>
>
> Following patches patches are against linux 2.5.7
>
>
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va01-knfsd-zerocopy-vfsre
ad-2.5.7.patch
>
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va02-kmap-multplepages-2.
5.7.patch
>
>
ftp://ftp.valinux.co.jp/pub/people/taka/tune/2.5.7/va03-knfsd-zerocopy-sendp
age-2.5.7-test1.patch
>
>
> Andrew, Could you try it again?
>
>
> Regards,
> Hirokazu Takahashi
>
>
> _______________________________________________
> NFS maillist - [email protected]
> https://lists.sourceforge.net/lists/listinfo/nfs
>
_______________________________________________
NFS maillist - [email protected]
https://lists.sourceforge.net/lists/listinfo/nfs
Hello,
I really appreciate your help!
> I tried the patch with great performance improvement! I ran my nfs read
> test (48 clients read 200 MB file from one 4-way SMP NFS server) and
> compared your patches to regular 2.5.7. Regular 2.5.7 resulted in 87 MB/sec
> with 100% CPU utilization. Your patch resulted 130 MB/sec with 82% CPU
> utilization! This is very good! I took profiles, and as expected,
> csum_copy and file_read_actor were gone with the patch. Sar reported nearly
> 40 MB/sec per gigabit adapter (there are 4) during the test. That is the
> most I have seen so far. Soon I will be doing some lock analysis to make
> sure we don't have any locking problems. Also, I will see if there is
> anyone here at IBM LTC that can assist with your development of zerocopy on
> UDP. Thanks for the patch!
I'd love to develop it with your team.
I have some ideas to implement it and I'm thinking about them.
Thank you,
Hirokazu Takahashi
_______________________________________________
NFS maillist - [email protected]
https://lists.sourceforge.net/lists/listinfo/nfs