lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 4 Jun 2013 11:40:59 +0300 From: Amir Vadai <amirv@...lanox.com> To: Eric Dumazet <eric.dumazet@...il.com> CC: David Miller <davem@...emloft.net>, netdev <netdev@...r.kernel.org> Subject: Re: [PATCH net-next] net/mlx4: use one page fragment per incoming frame On 03/06/2013 20:54, Eric Dumazet wrote: > From: Eric Dumazet <edumazet@...gle.com> > > mlx4 driver has a suboptimal memory allocation strategy for regular > MTU=1500 frames, as it uses two page fragments : > > One of 512 bytes and one of 1024 bytes. > > This makes GRO less effective, as each GSO packet contains 8 MSS instead > of 16 MSS. > > Performance of a single TCP flow gains 25 % increase with the following > patch. > > Before patch : > > A:~# netperf -H 192.168.0.2 -Cc > MIGRATED TCP STREAM TEST ... > Recv Send Send Utilization Service Demand > Socket Socket Message Elapsed Send Recv Send Recv > Size Size Size Time Throughput local remote local remote > bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB > > 87380 16384 16384 10.00 13798.47 3.06 4.20 0.436 0.598 > > After patch : > > A:~# netperf -H 192.68.0.2 -Cc > MIGRATED TCP STREAM TEST ... > Recv Send Send Utilization Service Demand > Socket Socket Message Elapsed Send Recv Send Recv > Size Size Size Time Throughput local remote local remote > bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB > > 87380 16384 16384 10.00 17273.80 3.44 4.19 0.391 0.477 > > Signed-off-by: Eric Dumazet <edumazet@...gle.com> > Cc: Amir Vadai <amirv@...lanox.com> > --- > drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h > index b1d7657..b1f51c1 100644 > --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h > +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h > @@ -98,11 +98,11 @@ > #define MLX4_EN_ALLOC_SIZE PAGE_ALIGN(16384) > #define MLX4_EN_ALLOC_ORDER get_order(MLX4_EN_ALLOC_SIZE) > > -/* Receive fragment sizes; we use at most 4 fragments (for 9600 byte MTU > +/* Receive fragment sizes; we use at most 3 fragments (for 9600 byte MTU > * and 4K allocations) */ > enum { > - FRAG_SZ0 = 512 - NET_IP_ALIGN, > - FRAG_SZ1 = 1024, > + FRAG_SZ0 = 1536 - NET_IP_ALIGN, > + FRAG_SZ1 = 4096, > FRAG_SZ2 = 4096, > FRAG_SZ3 = MLX4_EN_ALLOC_SIZE > }; > > Acked-By: Amir Vadai <amirv@...lanox.com> We are currently working on a patch to change the skb allocation scheme for the RX side, because the current mlx4_en architecture is behaving very bad when IOMMU is enabled. After this change, the driver will use one fragment, among other improvements. The most important will be fragments recycling to save alloc/free and dma_map/unmap. But, I think it will be a good idea to apply your fix now in case there will be delays. Thanks, Amir -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists