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ONTAP 7.2.5.1 Simulator & Slow writes

[ Edited ]

Anyone else seeing slow write speeds when using the netapp simulator??

 

I get the expected 100Mbit read speads... but it seems like its crawing along at 10Mbit when writing...

 

This is for NFS writes... Machines are on the same network.

 

Any thought Ideas would be great.

Re: ONTAP 7.2.5.1 Simulator & Slow writes

Hi Joseph,

How about the traffic on your LAN ? Did you find any time the packet drops ? You run “netdiag” to confirm no networking issues.

Thanks;

Daniel

Re: ONTAP 7.2.5.1 Simulator & Slow writes

danielpr wrote:

Hi Joseph,

How about the traffic on your LAN ? Did you find any time the packet drops ? You run “netdiag” to confirm no networking issues.

Thanks;

Daniel

Sorry, still a no go,

I am working on a separate segregated LAN so there is no other traffic,

There are no packet drops that I am seeing,

The slowdown that I am seeing is only when seen in the simulator.

If I start an NFS server on the machine I can send and receive at full speed, and seeing as this seems to only be affecting write speeds (I can read w/ no problems) I am thinking this may be a purpose buld limit of the simulator.

Results of the netdiag

NetappSIM-1> netdiag
Performing physical layer diagnostics.....OK
Performing network layer diagnostics.....OK
Performing transport layer diagnostics.....OK

NetappSIM-1>    

Thanks,

Joe

Re: ONTAP 7.2.5.1 Simulator & Slow writes

Hi Joe,

You can have a look at this kb https://now.netapp.com/Knowledgebase/solutionarea.asp?id=kb36582. And also worth looking into the CLI  O/P for nfs options.

Thanks

Daniel

Re: ONTAP 7.2.5.1 Simulator & Slow writes

danielpr wrote:

Hi Joe,

You can have a look at this kb https://now.netapp.com/Knowledgebase/solutionarea.asp?id=kb36582. And also worth looking into the CLI  O/P for nfs options.

Thanks

Daniel

Thanks Daniel, but Still no joy.

I've increased the "nfs.tcp.recvwindowsize" & "nfs.tcp.xfersize" to the max (65536), tried both TCP & UDP Protocols, tried adjusting the "rsize" & "wsize" on the client.

I've even gone as far as setting an NFS server on the Host machine to make sure its not the machine. (results below)

NFS from Client to Host

     dd if=/dev/zero of=/u06/test.file bs=8192 count=2048
     2048+0 records in
     2048+0 records out
     16777216 bytes (17 MB) copied, 1.795 seconds, 9.3 MB/s

NFS from Client to Simulator

     dd if=/dev/zero of=/u04/test.file bs=8192 count=2048
     2048+0 records in
     2048+0 records out
     16777216 bytes (17 MB) copied, 19.2495 seconds, 872 kB/s

Thanks for the Direction, but still stumped.

Joe C.

Re: ONTAP 7.2.5.1 Simulator & Slow writes

Hi Joe,

I tested it in RHEL server i dont find such delay in the NFS file copy.

Thanks

Daniel

Re: ONTAP 7.2.5.1 Simulator & Slow writes

Ok, I give up.

I've tried everything that I can think on.

3 different network cards, static / dhcp, even went as far as to connect the 2 machines directly via crossover.

and I still get the  same results... Blazing fast NFS transfers from the client to Simulator's Host IP... but dog slow when going to the Simulators IP.

It seems that I am cursed.

Re: ONTAP 7.2.5.1 Simulator & Slow writes

Ok Ok, So I didn't give up... But still having the Problem...

I've set up CIFS, and I still have the same slow 850K's writes...

I've Tried...

PC 2 VM(Sim)

VM 2 VM(Sim) same v-lan

VM 2 PC(Sim)

PC 2 PC(Sim) Direct via Crossover cable

Crux 2.5, CentOS 4 & 5, OULinux 4 & 5, RedHat 9

Broadcom TG3, 2x Intel E1000, 2x Intel E100

Even tried the ONTAP 7.3.1 Simulator w/ the same outcome.

Every install, Every combination results in the same 850KB's write speed.

Is there a setting that I am missing, some secret chant that I need to do???

I cannot believe that nobody out there doesn't see the same thing.

Anyone? Anyone?

Is this thing on?

Give me something Please!

Thank you,

Joe

Re: ONTAP 7.2.5.1 Simulator & Slow writes

Joe,

What about the memory size in Linux machine and how much you have shared it for Data ONTAP simulator?

It doesnt seems to be a network issue since you have tired with back to back also using cross over cable.

Thanks

Daniel

Re: ONTAP 7.2.5.1 Simulator & Slow writes

For the stand alone systems, there is 1 gig install w/ 512 allocated for the Netapp Simulator (There is no swapping as its the only thing running)

For the VM's, they are set to 2 gig w/ 512 allocated for the Netapp Simulator (Again no swapping as they are the only thing running)

I've also tried disabling HyperThreading in the standalone systems thinking its getting "stuck" in the hyperthreaded core... but that of course didn't help...

If you tell me that there is no network / write throttle then something has to I am doing... although I realy don't know what... the install is as simple as it can get....

Thank any way,

Cheers,

Joe