Bill Rees wrote: >Hi, > >I've got a appication I'm testing that writes millions >of 15K files to an 800gb raidset (5x160 gb Maxtor >drives on a 3ware 7450 controller). The basic format >of the directory structure is as follows: > >/partition/00/yyyymmdd/hhmm/file1 (15k) >/partition/00/yyyymmdd/hhmm/file2 (15k) >/partition/00/yyyymmdd/hhmm/file3 (15k) >. >. >. >/partition/00/yyyymmdd/hhmm/file1800 (15k) > >Where yyyymmdd is a date and hhmm is a time. My test >program simulates a production system. I'm writing >1800 files filled with nulls as fast as my CPU will >allow for each subdirectory in an effort to fill the >raidset. > >I compute the time in milliseconds that it takes to >fill a directory with the 1800 files. As the disk >fills, the number of megabytes the application can >write per second gradually degrades from around 8.5 >mb/sec when the disk is 2% full to 1.3 mb/sec at 23% >full. I tried the same test on a single 160gb disk >and, although the performance was a bit better, the >degradation is still there. A single 160gb formatted >with ext2 does not seem to show this gradual >degradation. > >Does this sound like normal behavior and does anyone >have a suggestion on what could be done to optimize >this? My production application can handle multiple >partitions so I could break up the 800gb raid. > >Any help or suggestions would be appreciated. > >Bill > > > > > >===== >Bill Rees - [EMAIL PROTECTED] - http://billrees.com > >__________________________________________________ >Do You Yahoo!? >Yahoo! Tax Center - online filing with TurboTax >http://taxes.yahoo.com/ > > This is a very interesting measurement. Please experiment with the patch to bitmap.c that Oleg is experimenting with (I think it was put on the reiserfs mailing list recently).
I think you will find the various mount options of interest. Hans
