From: Bert Deknuydt (Bert.Deknuydt@esat.kuleuven.ac.be)
Date: Fri Nov 14 2003 - 09:58:02 EST
Hello,
Has anyone encountered serious performance degradation when 'vfast' is
switched on? The manual claims it does its work without much impact, but
that's not what I experience.
-> On an XP1000, switching it on for the usr_domain (8 GB SCSI, 80% full)
eats 99% system time, virtually grinding the machine to a halt. I left
it running for 10 hours overnight, but it had still not finished or
entered regime.
-> On an DS20E, it saturates a HSG80 (170 GB SAN, 80% full), consuming 50%
system time (one of the two CPU's for 100%, I guess). Performance is
badly degraded, NFS is terrible; setting the "Percent IOs Allocated to
vfast When System Busy" to 0 (default is 1), seems to have no impact at
all.
This is on 5.1B PK3.
Am I the odd one out, or is 'vfast' really not ready for production?
Greetings, Bert.
-- ------------ eMail Bert.Deknuydt(at)esat.kuleuven.ac.be -------------- B.DeKnuydt, PSI-KULeuven Tel. +32-16-321880 Kasteelpark Arenberg 10 /| | || B-3001 Leuven-Heverlee _,_)| 4_|_|| FLANDERS, BELGIUM / . Fax. +32-16-321838 -------------- http://www.esat.kuleuven.ac.be/~deknuydt --------------
This archive was generated by hypermail 2.1.7 : Sat Apr 12 2008 - 10:49:44 EDT