We had an issue with our filer being very slow at times and found this:
filer> sysstat -x 1 CPU NFS CIFS HTTP Total Net kB/s Disk kB/s Tape kB/s Cache Cache CP CP Disk DAFS FCP iSCSI FCP kB/s in out read write read write age hit time ty util in out 92% 3661 0 0 3661 3381 29931 27615 0 0 0 3s 92% 0% - 11% 0 0 0 0 0 86% 3528 0 0 3528 1373 30761 28494 0 0 0 3s 90% 0% - 11% 0 0 0 0 0 86% 3581 0 0 3581 1393 31210 28744 0 0 0 3s 89% 0% - 12% 0 0 0 0 0 81% 2543 0 0 2543 2973 20125 20507 7285 0 0 3s 93% 65% T 32% 0 0 0 0 0 79% 3208 0 0 3208 1247 27981 25870 0 0 0 3s 89% 0% - 14% 0 0 0 0 0 89% 3659 0 0 3659 1416 31865 29340 0 0 0 4s 89% 0% - 11% 0 0 0 0 0 87% 3359 0 0 3359 3272 27305 25036 0 0 0 4s 93% 0% - 13% 0 0 0 0 0 90% 3671 0 0 3671 1428 32011 29592 0 0 0 3s 90% 0% - 13% 0 0 0 0 0 89% 3636 0 0 3636 1422 31639 29207 0 0 0 3s 89% 0% - 12% 0 0 0 0 0 89% 3462 0 0 3462 3319 28081 25796 0 0 0 3s 93% 0% - 14% 0 0 0 0 0 83% 3420 0 0 3420 1330 29825 27441 0 0 0 3s 89% 0% - 12% 0 0 0 0 0 87% 3552 0 0 3552 1381 30982 28555 0 0 0 3s 90% 0% - 12% 0 0 0 0 0 91% 3610 0 0 3610 3385 29472 27096 0 0 0 3s 93% 0% - 10% 0 0 0 0 0 79% 2818 0 0 2818 1096 24510 23864 4606 0 0 3s 89% 29% Ts 22% 0 0 0 0 0 71% 2602 0 0 2602 1015 22717 21671 4591 0 0 3s 89% 58% : 27% 0 0 0 0 0 90% 3632 0 0 3632 3381 29670 27266 0 0 0 4s 93% 0% - 10% 0 0 0 0 0 66% 2906 0 0 2906 1125 25341 23508 0 0 0 4s 90% 0% - 13% 0 0 0 0 0 76% 3474 0 0 3474 1339 29729 27604 0 0 0 4s 90% 0% - 10% 0 0 0 0 0 84% 3613 0 0 3613 3371 29431 27626 0 0 0 3s 93% 0% - 12% 0 0 0 0 0
NOTE: The "Cache age" is in seconds! (s) Anything under 2 minutes can cause filer slowdown.
NOTE: The FAS270 has a 2 core 650-MHz Broadcom BCM1250 CPU with 1 GB of ram.
PS: The FAS270 is to slow and not enough ram, and you can't upgrade it. We upgraded to a FAS3020 to resolve the issue. Boy is it a lot faster! There was a backup taking about 35 hours and it went down to less than 13. --------------------------------------------------------------------------------- NetApp Bug Report Bug ID 3986 Title
* In low memory situations, accessing files in large directories * (>5Mbytes) causes pauses in filer service
Duplicate of - Bug Severity 2 - System barely usable Bug Status Closed Product Data ONTAP Bug Type WAFL
Description Formatted
* When the cache age (as reported by the "sysstat" command) on a filer is * low (<2), and a user attempts to access a very large directory * (>5MBytes), file service may temporarily stall as the filer attempts to * load the directory into memory.
Workaround Formatted
*
Notes Formatted
* A more aggressive prefetch of large directories was implemented. This * should prevent performance problems.
Related Solutions
*
Fixed-In Version
* This bug is not scheduled to be fixed, you may opt to open a technical support * case if you would like to contact Network Appliance regarding the status of this bug.
Related Bugs
*
Bug Watch Status
* This bug is unwatchable.
************************************************************************ Glenn Marsh Lattice Semiconductor Corporation Senior Unix Systems Administrator 5555 NE Moore Court CAD Engineering Hillsboro, Oregon 97124 glenn.marsh@latticesemi.com 503-268-8000 503-268-8136 phone - 503-268-8459 fax ************************************************************************ NextPart_000_0064_01C82124.8FE70380--