hi,
I recently installed a Fedora Core2 distribution .
At the installation, i used the disk druid to make a raid0 Software cause i got 2 identicals disks (i got an HPT370 IDE RAID but i don't success to install hardware raid0 with the Fedora Core 2).
So after installation, i test the rate of the disk on the kernel 2.4.22 : Tiotest results for 4 concurrent io threads: ,----------------------------------------------------------------------. | Item | Time | Rate | Usr CPU | Sys CPU | +-----------------------+----------+--------------+----------+---------+ | Write 40 MBs | 0.6 s | 64.391 MB/s | 1.6 % | 41.9 % | | Random Write 16 MBs | 0.6 s | 27.075 MB/s | 0.0 % | 17.3 % | | Read 40 MBs | 0.1 s | 394.030 MB/s | 0.0 % | 98.5 % | | Random Read 16 MBs | 0.0 s | 399.351 MB/s | 0.0 % | 76.7 % | `----------------------------------------------------------------------' Tiotest latency results: ,-------------------------------------------------------------------------. | Item | Average latency | Maximum latency | % >2 sec | % >10 sec | +--------------+-----------------+-----------------+----------+-----------+ | Write | 0.033 ms | 40.530 ms | 0.00000 | 0.00000 | | Random Write | 0.023 ms | 4.379 ms | 0.00000 | 0.00000 | | Read | 0.010 ms | 1.983 ms | 0.00000 | 0.00000 | | Random Read | 0.009 ms | 0.428 ms | 0.00000 | 0.00000 | |--------------+-----------------+-----------------+----------+-----------| | Total | 0.020 ms | 40.530 ms | 0.00000 | 0.00000 | `--------------+-----------------+-----------------+----------+-----------'
It's "normal" performance about me... After i updraded to the kernel 2.6.x, and now this the new performance:
Tiotest results for 4 concurrent io threads: ,----------------------------------------------------------------------. | Item | Time | Rate | Usr CPU | Sys CPU | +-----------------------+----------+--------------+----------+---------+ | Write 40 MBs | 5.6 s | 7.105 MB/s | 0.0 % | 71.7 % | | Random Write 16 MBs | 3.6 s | 4.391 MB/s | 0.1 % | 99.0 % | | Read 40 MBs | 0.3 s | 148.692 MB/s | 0.7 % | 99.2 % | | Random Read 16 MBs | 0.1 s | 146.199 MB/s | 0.9 % | 98.2 % | `----------------------------------------------------------------------' Tiotest latency results: ,-------------------------------------------------------------------------. | Item | Average latency | Maximum latency | % >2 sec | % >10 sec | +--------------+-----------------+-----------------+----------+-----------+ | Write | 0.028 ms | 1.101 ms | 0.00000 | 0.00000 | | Random Write | 0.022 ms | 0.140 ms | 0.00000 | 0.00000 | | Read | 0.017 ms | 0.246 ms | 0.00000 | 0.00000 | | Random Read | 0.017 ms | 0.235 ms | 0.00000 | 0.00000 | |--------------+-----------------+-----------------+----------+-----------| | Total | 0.022 ms | 1.101 ms | 0.00000 | 0.00000 | `--------------+-----------------+-----------------+----------+-----------'
As u can see , the difference is so big, my raid 0 software on kernel 2.6.x has a rate lesser than a single disk...???
i made severals times the tests, and the results are the same...
The difference between my kernel 2.4.22 and 2.6.x is, that in 2.4.22 the loading of "raid0.o jbd.o and ext3.o" are doing by the initRD and in my 2.6.x the modules are built in the kernel (cause i don't success to create an initRD which works..:( )
What do you think a bout it ? The kernel 2.6.x is bad for raid0 or i make an error in installation ?
PS : sorry for my poor english ,and the bad chart
PS 2 : u can see a good displaying of the performance chart at this adress :
http://forums.zdnet.fr/viewtopic.php?f=8&t=31235
Thanks to help me. Bye
