Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a ESXi server (dual quad core, 8GB of DDR3 ram, 6x 1TB WD Blacks running in RAid 5 on the PErc 6/i controller.

I have a 64bit freenas VM running, on this VM I keep about 200Gigs of stuff that my windows machines access.

every now and then the throughput of this VM just dies, for example right now it can't even handle streaming a song and when I tried to transfer a folder the speed goes from 10-400KB/s.

Might I add at this point that the ESXi box has dual gigabit network cards plugged into a good solid gigabit switch and other linux and windows VM's are just fine I have seen speeds over 90MB/s (frequently)

The server still has ram left over (plenty actually) and cpu is very low (500-1000mhz)

any ideas what could cause this?



share|improve this question
Anything in the FreeNAS logs when it slows down like this? Also, are you connecting via FTP, CIFS, or something else? – nedm Sep 6 '10 at 3:22
I don't see anything in the system log, just a few normal items. I am using CIFS. the VM itself has 1GB of ram and access to 2 physical Cores (the server has 2x Intel 5520's) so it has plenty of power to serve up a few mp3's :) – Luma Sep 6 '10 at 4:22
it has nothing to do with networking, if you read my post you will see that I noted that I get speeds of over 90MB/s from other VM's on the same server and that the server is connected with 2x 1gigabit network adapters. you can't get 90MB/s with a 10/100. – Luma Sep 6 '10 at 21:24
If you haven't done so, under CIFS set the log level to 'Debug' and save/restart the CIFS service. Try another file transfer and then post the results. – nedm Sep 7 '10 at 18:38
good Idea, I will do that now. Thanks. – Luma Sep 7 '10 at 21:42
up vote 0 down vote accepted

The latest version of freenas now comes with openvm tools and so far it has been way better. I have not had any problems with related to this qustion.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.