Performance issues

[jugster]

I don't know if this is directly related to nas4free, but please shoot me down if it isn't.

So I have just setup a nas using nas4free. It has 2 2TB disk in a mirrored configuration using zfs. It is on a lan with three machines. On that lan I get approximately 50MB/s on my gigabit enabled router. I'm happy with that figure, but I know that the disks are capable indivudually of 100MB/s+, so theoretically I should be able to max out my gigabit intranet. That is not the performance issue I want help with, but if anyone can explain why this is so, I very much would appreciate that too =) (Probably the router pushing its limits)

On the same lan I have a windows machine. This is the machine the nas is replacing. The performance I get from that machine is about 33MB/s. It's a jbod setup, so transfer speed is limited to the individual disk, and they are quite old. Nothing odd about this figure I think.

Now to the strange thing.

This lan has a router, that is connected to another router via openvpn. Site to site openvpn over the Internet. All the machines on one side is accessible on the other side and vice versa. They are connected through a 10Mbit/s link.

If I transfer something from my windows machine through the openvpn network, I am able to max that connection out, I get some 1.2MB/s transfers.
If I try to access the newly built nas, I get about half that speed. Why is that?

It would seem to me that something that is almost twice as fast on the lan, should also be able to saturate the 10Mbit/s connection. I'm guessing that some setting that is alluding me plays a role in this. Anyone has any idea?

[danic]

How are you copying files? Via CIFS? (duh? this is the CIFS forum section...) Try a FTP transfer and see what you get. My NAS's CIFS performance over OpenVPN tunnels sucks as well. My solution was to enable the web server and use its directory listing to quickly navigate folders and grab files from my NAS.

My theory for the poor performance is that nas4free is tuned for 100mbit and gigabit networks. Also if your old server was Windows XP, its default SMB tuning is probably better for 10mbit and 100mbit networks. That's why windows xp performs better over your openvpn tunnel.

Play around with nas4free's ftp server and/or web server see if transfer performance is any better.

[jugster]

I am copying files via cifs on both machines obviously. Otherwise a comparison would be moot.
The windows machine is a windows 7 machine and not xp (does anyone actually use that anymore?)

Thanks for the tip though, I will try ftp and see if that changes things around, at least it will let me know if there are issues with the cifs configuration.

Also, I know that encrypting content though openvpn takes a great deal of cpu power (this is done by the router), but I don't see that those calculations should be any different just because the origin is different. The sam calculations needs to be made for the same file regardless where it comes from.

[jugster]

Having just tried enabling ftp I can say that there is a difference
1) From Win7 to Win7 over openvpn using cifs = 1.2MB/s (this is maxing out my 10Mbit/s connection)
2) From Nas4free to Win7 over openvpn using cifs = 0.5MB/s
3) From Nas4free to Win7 over openvpn using ftp = 0.6MB/s

4) From Nas4free to Win7 over lan using cifs = 50MB/s
5) From Nas4free to Win7 over lan using ftp = 70MB/s

So ftp is definately faster in all tests, for some reason though, it cannot manage to max out my 10Mbit/s connection. (It does clearly have the potential to do so as the lan tests prove)

[jugster]

Just had the opportunity to try my previous findings with Freenas and it is capable of maxing my 10mbit/s connection.

Clearly the disks are capable of delivering the bandwidth, but using nas4free it seems like the bandwidth is cut in half for some reason.

I don't know if it is important or not but my configuration is 2x2TB mirrored, 4GB Memory, P4 3.4GHz.

[danic]

What are your CIFS settings? I just did some testing and I only achieved 8-10mbit/s over my openvpn with CIFS.
I doubled the Send Buffer Size/Receive Buffer Size to 128480 and resulted in 30mbit/s (my link's top speed)

[jugster]

I have default settings, I have tried changing sendfile, aio on and off, also tried the old and the new protocol,but none of that makes any difference. I have not tried changing any numbers though, that will be my next thing. I'll let you know how it goes.

Testing this I imported the disk in freenas which does things a little bit differently it seems. And playing around with how to mount things again in nas4free I might have overwritten my entire collection of series and movies. Darn! Well, i guess that is what the Internet is for i guess.

I sure hope I can get the same performance out of nas4free as I get on Freenas, because it does seem a lot more stable. I'm having quite a few fatal crashes in freenas no matter which version I try or which configuration I have run. Nas4free just seem to work. Like it should.

[jugster]

I have now tried altering the size of the buffers, but it makes no difference.

I can see that some settings makes a performance difference when testing on the LAN, but when going through the router I still only get roughly half the performance of what max is (and what Freenas gives me).

I will continue to test this on every new version of nas4free that comes out, currently running the latest 775.

[jugster]

Tried same tests on a 804 build. Same issues persist. Only gets approximately half speed from cifs/ftp. I have 10mbit available, which is what I get from Freenas, but I only get half of that through Nas4free.

On the LAN I cannot see any problems, I get what I think I should be getting.

/J

[RedAntz]

Tried same tests on a 804 build. Same issues persist. Only gets approximately half speed from cifs/ftp. I have 10mbit available, which is what I get from Freenas, but I only get half of that through Nas4free.

On the LAN I cannot see any problems, I get what I think I should be getting.

/J

Hi jugster :-

SIFTU compiled a good performance troubleshooting list here :-
http://n4f.siftusystems.com/index.php/2 ... /comments/

[jugster]

Thank you, will explore options and report back.

[jugster]

Ok, running some iperf tests

1) nas to win8 (local):
nas4free: ~ # iperf -c 192.168.201.2
------------------------------------------------------------
Client connecting to 192.168.201.2, TCP port 5001
TCP window size: 257 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.201.6 port 63688 connected with 192.168.201.2 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 900 MBytes 755 Mbits/sec

2) nas to win7 (remote):
nas4free: ~ # iperf -c 192.168.200.7
------------------------------------------------------------
Client connecting to 192.168.200.7, TCP port 5001
TCP window size: 256 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.201.6 port 22770 connected with 192.168.200.7 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 5.00 MBytes 4.19 Mbits/sec

3) win8 to win7 (remote):
c:\Base>iperf.exe -c 192.168.200.7
------------------------------------------------------------
Client connecting to 192.168.200.7, TCP port 5001
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[152] local 192.168.201.2 port 60805 connected with 192.168.200.7 port 5001
[ ID] Interval Transfer Bandwidth
[152] 0.0-10.1 sec 11.3 MBytes 9.38 Mbits/sec

These tests show exactly what is happening to me.
1) Local bandwidth on my Gb network seems to be what I should expect.
2) Remote bandwidth, which means it goes through my routers through openvpn, notice how the ips are different (200 vs 201). Here I have half the available bandwidth of the connection. Available bandwidth is 10Mbit.
3) Repeating the test from another machine located on same network as the nas, connecting remotely to the same machine in test 2, I get nearly full bandwidth, which is what I would expect from nas4free and what I also get from Freenas (tested on same hardware, same disks, same content)

I'm no networking guy, but something needs configuring in nas4free. Also, it is uncanny how I'm able to get almost exactly half the available bandwidth.

This pattern is repeatable for any machine on the two networks. If I perform the test from the nas to any local computer, values are fine.From nas to any remote computer values are about half of what I should get. From any other machine than the nas to any computer on the other network I get full bandwidth. This seems confined to nas4free only.

Tips, anyone?

[Buhu]

what's your hardware ? AMD ?

[jugster]

Processor: Pentium 4 3.4GHz HT
Motherboard: Abit AW9D (Intel i975-ICH7)
Memory: 4GB random modules, that pass 1 month of continuous memtest testing (tested during vacation time‚ with no access to machine)
Harddrives: 2 Hitachi 2TB drives in mirror configuration.

Let me reiterate, exact same setup gets full bandwidth in FreeNAS.
However, I have not been able to get FreeNAS stable on only 4GB of memory.

[jugster]

Ran another iperf test on the new build, just for kicks... =)

Same setup, two lans connected by two routers. From the lan with the nas I executed this command "iperf -c 192.168.200.7"

On the other lan I executed this command "iperf -s"

These are the results:
c:\Setup>iperf -s
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
[248] local 192.168.200.7 port 5001 connected with 10.8.0.6 port 51285
[ ID] Interval Transfer Bandwidth
[248] 0.0-10.2 sec 11.8 MBytes 9.75 Mbits/sec
[268] local 192.168.200.7 port 5001 connected with 10.8.0.6 port 51286
[ ID] Interval Transfer Bandwidth
[268] 0.0-10.1 sec 11.8 MBytes 9.84 Mbits/sec
[276] local 192.168.200.7 port 5001 connected with 10.8.0.6 port 51287
[ ID] Interval Transfer Bandwidth
[276] 0.0-10.1 sec 11.2 MBytes 9.29 Mbits/sec
[264] local 192.168.200.7 port 5001 connected with 10.8.0.6 port 49755
[ ID] Interval Transfer Bandwidth
[264] 0.0-10.4 sec 6.00 MBytes 4.85 Mbits/sec
[268] local 192.168.200.7 port 5001 connected with 10.8.0.6 port 15722
[ ID] Interval Transfer Bandwidth
[268] 0.0-10.5 sec 6.13 MBytes 4.89 Mbits/sec
[260] local 192.168.200.7 port 5001 connected with 10.8.0.6 port 26387
[ ID] Interval Transfer Bandwidth
[260] 0.0-10.5 sec 6.13 MBytes 4.89 Mbits/sec

The three results that are on top are from a windows 8 machine to a windows 7 machine.
The three bottom results are from the nas on the same lan as the windows 8 machine (they stand right next to each other actually, connected through the switch on the router) to the very same windows 7 machine.

From the nas to the windows 8 machine I get:
[220] local 192.168.201.2 port 5001 connected with 192.168.201.6 port 62414
[ ID] Interval Transfer Bandwidth
[220] 0.0-10.0 sec 890 MBytes 745 Mbits/sec

With FreeNas I get full bandwidth utilization. But I refuse to use it for other reasons (crash prone on 4GB memory for me).

Are there any other tests I can run that might reveal some more information?
Or does anyone have a clue why nas4free behaves this way?