Messages in this thread | | | Date | Wed, 7 Jan 2004 20:06:07 +0100 (CET) | From | Guennadi Liakhovetski <> | Subject | Re: 2.6.0 NFS-server low to 0 performance |
| |
On Wed, 7 Jan 2004, Mike Fedyk wrote:
> On Wed, Jan 07, 2004 at 07:13:46PM +0100, Guennadi Liakhovetski wrote: > > noticed is that 2.6 is trying to read bigger blocks (32K instead of 8K), > > You mean it's trying to do 32K nfs block size on the wire?
Emn, no, if I understand it correctly. NFS-client requests 32K of data at a time, but that is sent in several fragments. Actually, client is the same (2.6 kernel), and it requests 32 or 8K depending on the kernel-version of the server...
> Just post a few samples of the lines that differ. Any files should be sent > off-list.
Well, I am afraid, I won't be able to identify the important differring packets. I did tcpdump -l -i eth0 -exX -vvv -s0 , so, the log contains complete packet dumps. Ok, I'll try just to quote headers. poirot is the server (PC1, 2.4 / 2.6), fast is the client (PC2, 2.6). Following the first request for data (diff only in length)
2.6:
18:42:28.374430 0:80:5f:d2:53:f0 0:50:bf:a4:59:71 ip 162: fast.grange.462443716 > poirot.grange.nfs: 120 read fh Unknown/1 32768 bytes @ 0x000008000 (DF) (ttl 64, id 15, len 148)
2.4:
18:48:57.794687 0:80:5f:d2:53:f0 0:50:bf:a4:59:71 ip 162: fast.grange.1972393156 > poirot.grange.nfs: 120 read fh Unknown/1 8192 bytes @ 0x000002000 (DF) (ttl 64, id 6, len 148)
the server (PC1) sends the following packets:
2.6:
18:42:28.374554 0:50:bf:a4:59:71 0:80:5f:d2:53:f0 ip 1514: poirot.grange.nfs > fast.grange.445666500: reply ok 1472 read REG 100644 ids 0/0 sz 0x00007a120 nlink 1 rdev 0/0 fsid 0x000000000 nodeid 0x000000000 a/m/ctime 1073497348.374212040 2477.000000 1064093242.000000 32768 bytes (frag 40553:1480@0+) (ttl 64, len 1500)
18:42:28.374560 0:50:bf:a4:59:71 0:80:5f:d2:53:f0 ip 1514: poirot.grange > fast.grange: (frag 40553:1480@1480+) (ttl 64, len 1500)
2.4:
18:48:57.806270 0:50:bf:a4:59:71 0:80:5f:d2:53:f0 ip 962: poirot.grange > fast.grange: (frag 39126:928@7400) (ttl 64, len 948)
18:48:57.806291 0:50:bf:a4:59:71 0:80:5f:d2:53:f0 ip 1514: poirot.grange > fast.grange: (frag 39126:1480@5920+) (ttl 64, len 1500)
Well, maybe important is this place in 2.6 log - when it got the first (2.5s) delay:
18:42:28.414903 1:80:c2:0:0:1 1:80:c2:0:0:1 8808 60:
18:42:31.033837 0:80:5f:d2:53:f0 0:50:bf:a4:59:71 ip 162: fast.grange.479220932 > poirot.grange.nfs: 120 read fh Unknown/1 32768 bytes @ 0x000010000 (DF) (ttl 64, id 18, len 148)
18:42:31.034244 0:50:bf:a4:59:71 0:80:5f:d2:53:f0 ip 1514: poirot.grange.nfs > fast.grange.479220932: reply ok 1472 read REG 100644 ids 0/0 sz 0x00007a120 nlink 1 rdev 0/0 fsid 0x000000000 nodeid 0x000000000 a/m/ctime 1073497351.33807720 2477.000000 1064093242.000000 32768 bytes (frag 40557:1480@0+) (ttl 64, len 1500)
So, does it say anything?
Thanks Guennadi --- Guennadi Liakhovetski
- 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/
| |