-------- Mensagem original -------- Assunto: Re:[CentOS] Filesystem for Maildir De: Christopher Chan <christopher at ias.com.hk> Para: CentOS mailing list <centos at centos.org> Data: terça-feira, 04 de dezembro de 2007 12:06:43 > Heitor A.M. Cardozo wrote: >> Christopher Chan wrote: >>> >>> ext3 again takes the slowest performing title overall as >>> expected...in fact it appears not much as changed fs vs fs wise >>> since Bruce Guenter's tests. >> I agree but the values are more "acceptable" in comparision with >> others filesystems. On Bruce tests it shows a very bad performance >> for reading. > > Yes, reads are vastly improved at the cost of write performance. > Weird. XFS has like the best read response times too. XFS is looking > very good at the moment with just about the fastest performance in > everything. What io-scheduler is default on Centos 5? I assume you > prefer read performance to write performance. After all, it is for > maildir use. Have you tuned the box for read performance? > Initially this box is not tuned for read because I would to compare the results of tests on default configuration with other configurations. The default io-scheduler on CentOS 5 is CFQ. >> >>> But I am surprised at the overall performance regressions in >>> comparison to 2.6.5/6 kernels with regards to deliveries vs amount >>> of writers.Heitor, you are using a 3ware 95xx or 96xx with BBU write >>> cache and write caching on right? How much RAM do you have for your >>> cache? How is your raid10 configured? I cannot believe a four disk >>> raid0 array can beat a software raid mirror of scsi disks as used by >>> Bruce Guenter. >>> >> 3ware 9650SE with BBU and write cache on. >> Available memory: 224 MB >> Bus Type/Speed: PCIe/2.5 Gbps >> RAID10: 4 RAID1 subunits with MAXTOR STM3500630AS 500GB SATA2 >> > > Yup, that is four disks versus a single linux mirrored scsi array. > Write performance cannot be that horrible now can it? > Sorry, i forgot to say that the stripe size is set at 64Kb, not that this explain the bad write performance. I will configure and initilize array again and repeat one test to check. >>> >>> Thanks Heitor. Is the site down or something? I cannot access the >>> page....it is timing out. >> The site is online now. >> > > thanks. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos