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The Graveyard - Products No Longer Supported => D-Link Storage => DNS-323 => Topic started by: heartog on July 28, 2011, 08:37:17 AM

Title: Jumbo Frames slows transfer speeds
Post by: heartog on July 28, 2011, 08:37:17 AM

when i enable jumbo frames, the transfer speed dropped from 14mb/s to 9mb/s. i want to know why do i have 14mb/s speed while i have a gigabit connection

Title: Re: Jumbo Frames slows transfer speeds
Post by: dividedhighw on July 28, 2011, 08:41:25 AM

Just checking - you have Jumbo frames enabled on the client side too, right?

Cheers,
DH

Title: Re: Jumbo Frames slows transfer speeds
Post by: Flamingfarts on July 28, 2011, 08:45:04 AM

also if you use network switches on your network make sure that they support Jumbo frames or it will never work even if both client is Jumbo frames enabled.

Title: Re: Jumbo Frames slows transfer speeds
Post by: heartog on July 28, 2011, 08:46:57 AM

i have enabled jumbo frames on the client and my switch support jumbo frames.

Title: Re: Jumbo Frames slows transfer speeds
Post by: fordem on July 28, 2011, 10:56:01 AM

What do you really want to know - why the speed drops with jumbo frame or why you have 14mb/s with a gigabit connection?

1st question - 14 megabits/second or 14 megaBYTES/sec?

14 MegaBYTES/sec is roughly 140 megabits/sec, which since it is over 100 megabits/second technically is gigabit speed - you cannot get that on a hundred megabit connection.

If your question is why is it so slow - try searching - theat is the most beaten to death topic in this forum - you bought a device advertised at upto 23MB/sec, so you knew it was slow, and you've asked this question before and gotten the same answer.

Title: Re: Jumbo Frames slows transfer speeds
Post by: heartog on July 28, 2011, 12:24:31 PM

mainly my question is why does the speed drop when i enable jumbo frames. i hvae 14 Megabytes/s

Title: Re: Jumbo Frames slows transfer speeds
Post by: fordem on July 28, 2011, 04:05:50 PM

For jumbo frame to work properly, the entire network PATH between the two devices needs to support jumbo frame up to the frame size you wish to use - so, you have the two end points - the DNS-323 and the computer, and the network linking them, which is going to be at minimum two cables and a switch or router.

What size frame does the switch/router support?
What size frames do the DNS-323 and computer support?

The switch frame size can be larger than the other two, but never smaller.

Next - how are you testing?

Jumbo frame is only worth the trouble if the file sizes involved are large enough to make it worth your while.

Title: Re: Jumbo Frames slows transfer speeds
Post by: heartog on July 28, 2011, 05:15:10 PM

dns 323 max support is 9000 and my pc is 9014. the switch supports 9216.

Title: Re: Jumbo Frames slows transfer speeds
Post by: Steve Pitts on July 29, 2011, 05:42:56 AM

If any device in the network route does not support jumbo frames of the size being sent then those packets will be fragmented, which will slow transmission speeds. Do you have a lower value supported by all the devices involved that you could try (say 7000)?? If you issue a

Code: [Select]

ping -f -l 9000 nas_name_or_ip_address
what do you get back??

Title: Re: Jumbo Frames slows transfer speeds
Post by: Flamingfarts on July 29, 2011, 08:21:07 AM

just for sharing : with jumbo frame enabled at 9K im getting 33 Mb/sec reading and 12Mb/sec writing with two segate 1 TB in raid 1

Title: Re: Jumbo Frames slows transfer speeds
Post by: dividedhighw on July 29, 2011, 10:48:53 AM

Quote from: Flamingfarts on July 29, 2011, 08:21:07 AM

just for sharing : with jumbo frame enabled at 9K im getting 33 Mb/sec reading and 12Mb/sec writing with two segate 1 TB in raid 1

Mind saying what exact model of drive?

TIA!
DH

Title: Re: Jumbo Frames slows transfer speeds
Post by: heartog on July 29, 2011, 12:56:46 PM

drive: seagate ST2000DL003
what do you mean by network route?

Title: Re: Jumbo Frames slows transfer speeds
Post by: Flamingfarts on July 29, 2011, 01:01:07 PM

Quote from: dividedhighw on July 29, 2011, 10:48:53 AM

Mind saying what exact model of drive?

TIA!
DH

here you go : Seagate Barracuda ST31000524AS 7200.12 1TB SATA 32MB Cache

Title: Re: Jumbo Frames slows transfer speeds
Post by: dividedhighw on July 30, 2011, 05:42:34 PM

Quote from: heartog on July 29, 2011, 12:56:46 PM

drive: seagate ST2000DL003
what do you mean by network route?

The term "network route" used in this context refers to the complete path taken by the packets from the client/host through all intervening devices, to the your DNS-323 NAS and back again (in a small LAN, the return path would likely be the same path, but in reverse).

HTH,
DH

Title: Re: Jumbo Frames slows transfer speeds
Post by: dividedhighw on July 30, 2011, 05:43:20 PM

Quote from: Flamingfarts on July 29, 2011, 01:01:07 PM

here you go : Seagate Barracuda ST31000524AS 7200.12 1TB SATA 32MB Cache

Thx!  DH

Title: Re: Jumbo Frames slows transfer speeds
Post by: heartog on July 31, 2011, 07:17:04 AM

that is my os drive