Date: Sun, 6 Jul 1997 00:53:52 -0500 (CDT) From: "Mark W. Krentel" <krentel@cs.rice.edu> To: freebsd-hackers@freebsd.org Subject: NFS v3 slower than v2 Message-ID: <199707060553.AAA05251@new-world.cs.rice.edu>
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I suspect there is a bug in the nfs code causing nfs3 to perform
somewhat slower than v2. It doesn't fall over dead, but I can
produce examples where v3 takes twice as long as v2.
Here's a simple way to reproduce the problem. First, create a
large tar file. I used /usr/src/sys, about 24 meg, 2300 files.
For each test, unpack the tar file on the server, so the freebsd
client can't use its cache (is there a recursive touch?). In my
case, the server is an Ultrasparc/Solaris 2.5.1 with 100 MB link.
Then, read the new directory with:
% nfsstat ; time tar cf - sys > /dev/null ; nfsstat
I tried this three times each, mounting the same partition under
v2 and v3. V2 took 10.6, 13.5 and 8.8 seconds wall clock time,
but v3 took 24.0, 21.0 and 22.1. Looking at the diffs of nfsstat,
everything is the same for v2/v3, except v3 produces a large number
of Accesses, but v2 produced none.
I see a similar problem for writes, but the effect is smaller.
1. What is Access in nfsstat?
Is it a symptom of trouble for reads?
2. Can anyone else verify this problem, or is it known?
For all I know, it may be specific to Solaris servers and
Freebsd clients with 100 MB link.
Mark Krentel
Rice University
krentel@cs.rice.edu
Hardware: 200 MHz PPro (512K cache), Intel Venus board, 128 meg RAM,
Adaptec 2940U, SMC 9332 100 MB ethernet.
This is version 2:
Client Info:
Rpc Counts:
Getattr Setattr Lookup Readlink Read Write Create Remove
27299 4209 15235 117 8602 13999 1969 2038
Rename Link Symlink Mkdir Rmdir Readdir RdirPlus Access
718 5 7 195 192 640 0 138327
Mknod Fsstat Fsinfo PathConf Commit GLease Vacate Evict
0 14 13 0 1861 0 0 0
Rpc Info:
TimedOut Invalid X Replies Retries Requests
0 0 6 70 215440
Cache Info:
Attr Hits Misses Lkup Hits Misses BioR Hits Misses BioW Hits Misses
288424 27299 148601 13805 42147 8602 3419 13999
BioRLHits Misses BioD Hits Misses DirE Hits Misses
13794 117 5000 632 1148 0
0.061u 1.225s 0:10.62 12.0% 336+401k 0+1io 3pf+0w
Client Info:
Rpc Counts:
Getattr Setattr Lookup Readlink Read Write Create Remove
29545 4209 17512 120 12626 13999 1969 2038
Rename Link Symlink Mkdir Rmdir Readdir RdirPlus Access
718 5 7 195 192 727 0 138327
Mknod Fsstat Fsinfo PathConf Commit GLease Vacate Evict
0 14 13 0 1861 0 0 0
Rpc Info:
TimedOut Invalid X Replies Retries Requests
0 0 6 70 224077
Cache Info:
Attr Hits Misses Lkup Hits Misses BioR Hits Misses BioW Hits Misses
330444 29545 163947 16082 44208 12626 3419 13999
BioRLHits Misses BioD Hits Misses DirE Hits Misses
13794 120 5082 718 1231 0
This is version 3:
Client Info:
Rpc Counts:
Getattr Setattr Lookup Readlink Read Write Create Remove
29647 4209 17552 123 12645 14022 1970 2038
Rename Link Symlink Mkdir Rmdir Readdir RdirPlus Access
718 5 7 195 192 736 0 138397
Mknod Fsstat Fsinfo PathConf Commit GLease Vacate Evict
0 14 14 0 1864 0 0 0
Rpc Info:
TimedOut Invalid X Replies Retries Requests
0 0 6 72 224348
Cache Info:
Attr Hits Misses Lkup Hits Misses BioR Hits Misses BioW Hits Misses
330749 29647 164052 16122 44248 12645 3453 14022
BioRLHits Misses BioD Hits Misses DirE Hits Misses
13831 123 5094 726 1241 0
0.084u 2.272s 0:24.03 9.7% 276+328k 0+1io 0pf+0w
Client Info:
Rpc Counts:
Getattr Setattr Lookup Readlink Read Write Create Remove
31892 4209 19829 126 16669 14022 1970 2038
Rename Link Symlink Mkdir Rmdir Readdir RdirPlus Access
718 5 7 195 192 823 0 155988
Mknod Fsstat Fsinfo PathConf Commit GLease Vacate Evict
0 14 14 0 1864 0 0 0
Rpc Info:
TimedOut Invalid X Replies Retries Requests
0 0 8 74 250575
Cache Info:
Attr Hits Misses Lkup Hits Misses BioR Hits Misses BioW Hits Misses
355179 31892 179398 18399 46309 16669 3453 14022
BioRLHits Misses BioD Hits Misses DirE Hits Misses
13831 126 5176 812 1324 0
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