raid3 is slow

[R. B. Riddick]

--- Szabó Péter <matyee at mail.alba.hu> wrote:
> Array problem solved. But my problem is not the low read/write performance, 
> my problem is the high load. I start a single bittorrent download to the 
> encoded raid3 partition with 2.5MB/s speed, and the load is 2.5.
> 
Hmm...

As far as I can see it, u have the following tasks:
1. talking to the disks
2. label-related stuff
3. graid3 related stuff (splitting-up requests, XOR-ing all data)
4. gbde related stuff (encoding)
5. apllication stuff
6. network stuff

You can see, how those tasks load ur CPU(-s(?)), when u use this command:
  top -S
during this download process...

The output of
  systat -vmstat
during the download process might be quite interesting, too...

You may want to do the download to another disk or to /dev/null somehow (in
order to exclude the influence of graid3)...

-Arne


 
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