NFS Performance: Weirder And Weirder

[Mehmet Erol Sanliturk]

On Sat, Mar 16, 2013 at 6:46 PM, Tim Daneliuk <tundra at tundraware.com> wrote:

> On 03/16/2013 05:43 PM, Mehmet Erol Sanliturk wrote:
>
>>
>>
>  Michael  W. Lucas in Absolute FeeBSD , 2nd Edition ,  ( ISBN :
>> 978-1-59327-151-0 ) ,
>> is suggesting the following ( p. 248 ) :
>>
>> In client ( mount , or , fstab ) , use options ( -o tcp , intr , soft ,
>> -w=32768 , -r=32768 )
>>
>> tcp option will request a TCP mount instead of UDP mount , because
>> FreeBSD NFS defaults to running over UDF .
>>
>> This subject may be another check point .
>>
>>
>
> Another very good suggestion but ... to no avail.  Thanks for pointing
> this out.
>
> --
> ------------------------------**------------------------------**
> ----------------
> Tim Daneliuk     tundra at tundraware.com
> PGP Key:         http://www.tundraware.com/PGP/
>
>

I have read messages once more .

There is a phrase : Linux Mint 12 machineS ( plural ) .

In your descriptions , there is no any information about network setup :

Single client ,
multiple clients , etc .

Then , with some assumptions :

If there is ONLY ONE client , and all of the tests are performed on this
ONLY client ,
problem may be attributed to FreeBSD server or kind of file(s) in different
directories :
One of the is encrypted ( requires decryption ) , another is plain file ,
etc. .

If there is MORE than ONE client , problem may be attributed to any one the
components of the network ( server , clients , switch , cable , NICs ,
interfering other software , etc. ) .

Assume there is MULTIPLE clients :


Take two clients of them :

(A) Client 1 : Mount two directories .
(B) Client 2 : Mount two directories .

Test transmission performance :

If they are similar , inspect server settings , directory privileges , etc
. , file systems ( one is ZFS , other is UFS2 , etc. ) . All of the
hardware may work properly , but if the file reading is not able to feed
NIC sufficiently fast , it may show up as degraded performance .
Increasing NIC buffer size ( as standard it is around 1000 bytes ) to
maximum available , may
offset latency of supply of data to NIC .

If they are different : Check client specialties :

A cable may be CAT5 ( only maximum 100 Mbits transfer . Network cards are
adaptive , they try 1 Gbits , if it is not achievable , it reduces to speed
to 100 Mbits , even to 10 Mbits ) .
In that case either use CAT6 cable or CAT5x ( for 1 Gbit transmission , I
do not remember x now )
The cable kind should be written on cable , if it is not written , select a
properly labelled cable .

Interchange cable tips to clients : If performance interchanges also :
Cable or SWITCH port is faulty :

Check switch port : It may be a 100 Mbits  , be sure that it is also 1
Gbits and working properly .


Mehmet Erol Sanliturk