DNS-323 Alt-F transfer speed

[J. Lukasser]

Hi!

Have build in in my PC today a Netgear 1Gbit Lan Card and i do not understand the transfer speed to the DNS-323.

All the systems now running with 1Gbit Lan, i think the DLink also, or?

I test the transfer with a 4GB file:

PC to Laptop > 88MB/Sec

Laptop to PC > 88MB/Sec

PC to NAS > 12MB/Sec

Laptop to NAS > 12MB/Sec

NAS to PC > 12MB/Sec

NAS to Laptop > 12MB/Sec

All systems connectet about a Netgear GS108, and on the Switch it is showing that all connected with 1Gbit.

I have replaced the Lan cable but no change.

12MB/Sec is also the ident transfer speed what i have with my old 100Mbit Lan Card.

In the System overview at Alt-F is displaying Speed 1000Mbps, but i think this is not right?

So my question is, must i set anything on my DNS-323 or Alt-F that the transfer speed from the NAS is higher?

THANKS :)

[João Cardoso]

On Friday, November 28, 2014 8:09:03 PM UTC, J. Lukasser wrote:

Hi!

Have build in in my PC today a Netgear 1Gbit Lan Card and i do not understand the transfer speed to the DNS-323.

All the systems now running with 1Gbit Lan, i think the DLink also, or?

I test the transfer with a 4GB file:

PC to Laptop > 88MB/Sec

Laptop to PC > 88MB/Sec

PC to NAS > 12MB/Sec

Laptop to NAS > 12MB/Sec

NAS to PC > 12MB/Sec

NAS to Laptop > 12MB/Sec

All systems connectet about a Netgear GS108, and on the Switch it is showing that all connected with 1Gbit.

I have replaced the Lan cable but no change.

12MB/Sec is also the ident transfer speed what i have with my old 100Mbit Lan Card.

In the System overview at Alt-F is displaying Speed 1000Mbps, but i think this is not right?

It is right.

Your box is like having a fiat 600 running on a six lane highway -- have you noticed the ferrari that has just surpassed you? It's feed by the same fuel as your fiat 600, and yet...

[J. Lukasser]

Okay, but if I go with my fiat 600 on the highway, I do not want to drive the speed of the country road :)

So, if i buy a gigabit NAS i do not understand why the transfer speed is the same, whether I adjusting 100MBit or 1000MBit on my lan card :(

But i think that is no Alt-F problem, and so can this firmware not solve the problem from DLink?

In the original Firmware does it give a setting for transfer speed AUTO - 100 - 1000, does it that give also in Alt-F?

THANKS :)

[Chris Sarbora]

I am noticing the same issue. I have a 323 and a Macbook Pro both wired to a gigabit switch, with the switch indicating a full 1000BaseT connection to both devices. Transfer speed between them, however, is abysmal - my test is transferring 2160 mb in an average of 3m43s - that's 9MB/s, or just 77.5 mbit/sec. The network hardware on the NAS clearly supports gigabit link as indicated by the switch, the hard drive inside the NAS (Hitachi HTS725050A9A362) is quite capable of saturating a gigabit link, so the bottleneck must lie somewhere between the two - aka, in the software.

[Chris Sarbora]

I'll also add - during my transfer tests, the system health on the NAS gets demolished. 100% CPU utilization, near 100% RAM usage, and load averages jump from an idle 0.2 to 4.0 and higher. Something is either reading or writing extremely inefficiently.

[Chris Sarbora]

One last addition - it appears to be something in the network driver, firmware or hardware. I ran a bunch of tests to try to isolate the subsystem that was bottlenecking. The kernel's I/O capacity appears to peak out at around 425 MB/sec, based on dd'ing from /dev/zero to /dev/null. The disk's non-burst sequential read throughput, contrary to my prior post, appears to peak out at about 50 MB/sec (400mbps), which from what I'm reading seems fairly standard for the type of drive it is. Both of these numbers are still about an order of magnitude higher than the ~9 MB/sec I'm seeing over the network, however. I wrote a pair of test programs that pipe 400MB of zeros from a server to a client and time it - bingo, that's where the bottleneck is: 400MB in 44.801 sec = about 75 Mbps, exactly the rates I'm seeing for file transfers. Changing network cables had no effect, and the switch is quite capable of sustaining a reliable 900+ mbps between other hosts.

Either the hardware link is lying about its 1000T capability, or something is amiss in the Alt-F driver I think.

[Chris Sarbora]

Very interesting, ok. Thanks for the further information, and for adding this topic to the FAQ - I did look for previous questions/solutions but this thread was the only thing I could find, so that FAQ entry will likely become more and more important as people migrate to gigabit networks.

On Saturday, November 29, 2014 7:00:54 PM UTC-8, João Cardoso wrote:

The point is that the box has not enough CPU power: network +  filesystem + eventually *software* RAID + disk. That's it.

D-Link is not lying when it said that the box is GB capable -- it is, what it can't do is to saturate the link.

You can try to use iperf or netperf, which I made available as Alt-F packages exactly because this transfer speed "issue" has been discussed ad nausea before (search the forum for it). Using iperf you can separated network and disk subsystems with a tested/reliable benchmarking tool [added: -- but remember, the reported throughput is attained at almost 100% CPU utilization, meaning that the CPU can't do other tasks such as reading or writing to disk.]

You can also increase the MTU and see how it affects throughput [added: Jumbo frames appeared to alleviate the CPU from the network software overhead, see eg this  and this. Quote:

One of the early drivers for using jumbo frames was limited CPU speed. As I noted earlier, it takes over 80,000 standard Ethernet frames per second to fill a gigabit Ethernet pipe, which is a lot of CPU cycles. PCs with slower CPUs and bus speeds could not generate and pump enough Ethernet frames to fully utilize gigabit Ethernet's bandwidth. So network performance gains of 50% (!) were realized with jumbo frames on PCs with slower CPUs and bus speeds than the PCs in use today.

]

This post is particularly interesting: https://groups.google.com/d/msg/alt-f/h95CmLrT_RI/7-Rmp6hJZVQJ

Here you have some benchmarks on the stock firmware: http://dns323.kood.org/information:benchmarks

I will not embrace on discussing this "issue" again. [added: and just added a "why is it so slow" entry in the FAQ, hope that's definitive]

[J. Lukasser]

Hi :)

Theoretically asked:

You write "eventually *software* RAID", so could i have mor transfer speed if i do not use RAID1, and set the NAS to JB0D?

It may be possible, to disable any function or plugin to have more transfer speed?

THANKS :)

[João Cardoso]

On Tuesday, December 2, 2014 7:26:35 AM UTC, J. Lukasser wrote:

Hi :)

Theoretically asked:

You write "eventually *software* RAID", so could i have mor transfer speed if i do not use RAID1, and set the NAS to JB0D?

search for " Filesystem and disk layout performance on 0.1B4" in this forum

JBOD has *zero* security, lower than a "standard" filesystem, search for JBOD in this forum

[J. Lukasser]

Can anyone say me if the LAN speed from the DNS-320 or DNS-320L is faster?

[Michael Schieke]

Am Freitag, 5. Dezember 2014 20:37:48 UTC+1 schrieb J. Lukasser:

Can anyone say me if the LAN speed from the DNS-320 or DNS-320L is faster?

 DNS-320L with mint Alt-F about 40MB/s.

[J. Lukasser]

Knows anyone the speed of a "normal" DNS 320?

[João Cardoso]