Dear Christoph, In message <20110125171017.GA24921@xxxxxxxxxxxxx> you wrote: > > > There may be 20...50 millions of files, or more. 65% of the files are > > smaller than 4 kB; 80% are smaller than 8 kB; 90% are smaller than 16 > > kB; 98.4% are smaller than 64 kB. > > I don't think you even want a RAID0 in that case. For small IOPs > you're much better off with a simple concatenation of devices. What exactly do you mean by "conatenation"? LVM striping? At least the discussion here does not show any significant advantages for this concept: http://groups.google.com/group/ubuntu-user-community/web/pick-your-pleasure-raid-0-mdadm-striping-or-lvm-striping > > Should I do anything different to acchive maximum performance? > > Make sure to disable the disk write caches and if not using the newest > kernel also mount the filesystem with -o nobarrier. With lots of small > I/Os and metadata intensive workloads that's usually a lot faster. Tests if done recently indicate that on the other hand nobarrier causes a serious degradation of read and write performance (down to some 40% of the values before). > Also if you have a lot of log traffic an external log devices will > help a lot. It's doesn't need to be larger, but it will keep the > amount of seeks on the other devices down. Understood, thanks. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@xxxxxxx Never underestimate the bandwidth of a station wagon full of tapes. -- Dr. Warren Jackson, Director, UTCS -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
