Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Very high IRQ load causing horrible iSCSI performance
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware
View previous topic :: View next topic  
Author Message
dinominant
n00b
n00b


Joined: 27 Oct 2006
Posts: 62

PostPosted: Mon Oct 08, 2012 9:28 pm    Post subject: Very high IRQ load causing horrible iSCSI performance Reply with quote

I've setup a RAID6 iSCSI target on a Gentoo system. When I read data with the initiator I see ~100MBps on each network adapter. It's excellent because the bottleneck is the ethernet port and not the RAID array. However when I try to write to the array (via iSCSI) I see huge system CPU load and the performance drops to ~2MBps.

I'm suspecting it's related to a large amount of interrupts flooding the CPU and the system has no time to do anything but get interrupted.

What can I do to fix this -- or even verity that the IRQ load is the problem??
_________________
BTC: 18wdrw8sLtruvdwr5kB3RxbbxzjDeXUpRh
LTC: LYynwaSeBLb4gHaMnkB7NQ27H6wF3Fjyxo
Back to top
View user's profile Send private message
dinominant
n00b
n00b


Joined: 27 Oct 2006
Posts: 62

PostPosted: Wed Oct 10, 2012 3:51 pm    Post subject: Reply with quote

Due to time constraints I will have to revisit this problem at a later date. I did have better performance and I believe the issue was an MTU mismatch between the target and the initiator but I cannot verify that this was the case until I can spend some more time on this system.
_________________
BTC: 18wdrw8sLtruvdwr5kB3RxbbxzjDeXUpRh
LTC: LYynwaSeBLb4gHaMnkB7NQ27H6wF3Fjyxo
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum