odd transfer rates

[creepwood]

I'm getting what I feel is odd numbers on transfer rates.
I have a RAIDZ setup with 4x2tb Western Digital green drives.
I started fiddling with this because I don't get more than 25mb/sec over samba from my workstation.

To see if it has anything to do with the Freenas I did

Code:

dd if=/dev/zero of=/mnt/panda/testfile bs=8192k count=1000

in the SSH terminal. I got "decent" numbers of about 120 mb/sec. But from what I can make out of checking the processes the DD process never breaks 20%. I use 6GB of RAM and an "old" Celeron CPU, Celeron 430 @ 1800 mhz

the SATA controller is integrated on the MOBO, Intel ICH9, could this really be the bottleneck?

ofc 120 mb/sec is not the issue anyway because I won't be reaching that over the gigabit network anyway.

I'd like to optimize LAN transfers, reading on the forums about different ideas but aren't getting any wiser.

 

[matthewowen01]

first up an 8 GB file is not large enough to test with, do at least 50. most of your memory is used for cache so writing an 8 GB file is mostly able to fit in memory, not the actual performance of the drives for a single contiguous write operation. let me know how fast that goes.

second, when your testing over samba, is it one large file or many small ones, small files transfer pretty badly over samba in general?

are you using the x64 or the x32 version of freenas?

 

[creepwood]

Sorry for not specifying more. I'm using x64 version, 8.0.1 beta 4.

when testing through samba it's usually large file.

Are you sure you're meaning 8 and 50 gigabyte files? I was trying with 8 megabyte files (according to the DD test) Maybe I'll try 50gb files but not a 1000 times? :P

 

[sjieke]

The test you performed wrote a file of about 8GB, using block sizes of 8MB.

dd if=/dev/zero of=/mnt/panda/testfile bs=8192k count=1000

bs stands for block size and count says how many blocks you want to write. So 8MB * 1000 = 8000MB = 7.8GB ~ 8GB

What matthewowen01 tries to tell you is that you need to write files of at least 50GB to remove the cache (your RAM) from the measurement.

A dd command can be:

dd if=/dev/zero of=/mnt/panda/testfile bs=2M count=25000

So write a file in 25000 blocks of 2MB: 2MB *25000 = 50000 MB = 48.8GB ~ 50GB

 

[creepwood]

Aight, I tried that. getting speeds of 140MB/sec CPU usage is around 20%, peeking out around 24%

 

[sjieke]

Does are good results. Here is what I get with my hardware (4GB RAM, ATOM D525, 4 x 2TB in RaidZ1)

Write
1GB 2GB 5GB 10GB 20GB 50GB

1301.3 140.5 134.0 104.0 112.2 96.7
2405.4 188.5 116.1 122.8 109.6 107.2
3343.7 179.6 127.2 114.5 111.4 111.8
4141.2 131.8 152.3 118.1 112.8 110.1
5333.3 206.4 112.3 115.3 109.8 108.0

Avg 305.0 169.4 128.4 115.0 111.2 106.8

Read
1GB 2GB 5GB 10GB 20GB 50GB

1 167.3 114.7 193.0 160.1 119.9 163.5
2 138.3 145.7 172.3 175.0 160.5 167.9
3 191.3 126.6 193.7 178.3 185.3 162.7
4 92.8 175.8 177.3 177.9 153.3 179.5
5 175.8 146.7 154.3 170.9 184.1 181.2
Avg 153.1 141.9 178.1 172.5 160.6 171.0

I used the same dd command as mentioned previously. Just altered the count for the different file sizes

 

[matthewowen01]

Aight, I tried that. getting speeds of 140MB/sec CPU usage is around 20%, peeking out around 24%

those speeds seem pretty decent for the hardware. can you try copying 1 Large file over the network and let us know how that goes?

 

[marcusmarcus]

If it helps. I used LAN Speed Test to test my transfer rates over the network. It let me set the file size, then it tested the write and read speed to the location I selected and then reported back the speed of both. I ran it between each tweak I mad on my FreeNAS to figure out if the tweak helped or hindered the transfer speeds.

http://www.totusoft.com/lanspeed1.html

 

[creepwood]

those speeds seem pretty decent for the hardware. can you try copying 1 Large file over the network and let us know how that goes?

I'm on vacation until early next week so I'll have to wait.