[SOLVED] ramdisk speed

[mister_thew]

Hi All,

 

still trying to diagnose my speed issues with a Dell R750 dual Gold CPU 1Tb memory NVME, etc

 

tested alot and my final test i think i have gotten to is  a fresh reboot and not start the array. I have then done a dd test to the ramdisk and i would have expected better speeds?

 

Writing to the 18 disk array i get about 10-15MB and reading i get 20-30MB

 

Installed windows server 2022 as a test and speeds are fine can max out the 10GB nics...

Edited November 10, 2022 by ocexperts

[Vr2Io]

You have 1TB memory ?

 

Below is test on a Intel J1900 and 9700k system

 

time dd if=/dev/zero bs=1024k of=tstfile count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 1.72748 s, 622 MB/s

real    0m1.736s
user    0m0.014s
sys     0m1.708s

 

/dev/shm# time dd if=/dev/zero bs=1024k of=tstfile count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.454901 s, 2.4 GB/s

real    0m0.458s
user    0m0.002s
sys     0m0.454s

 

How about to /dev/null ?

 

time dd if=/dev/zero bs=2M of=/dev/null count=1024
1024+0 records in
1024+0 records out
2147483648 bytes (2.1 GB, 2.0 GiB) copied, 0.530346 s, 4.0 GB/s

real    0m0.539s
user    0m0.019s
sys     0m0.516s

 

time dd if=/dev/zero bs=2M of=/dev/null count=1024
1024+0 records in
1024+0 records out
2147483648 bytes (2.1 GB, 2.0 GiB) copied, 0.131551 s, 16.3 GB/s

real    0m0.140s
user    0m0.006s
sys     0m0.134s

 

 

Edited November 10, 2022 by Vr2Io

[mister_thew]

Thanks for the reply Vr2Io but i just worked it out.. kinda

i disabled 14 of the 16 dim slots via bios and its now freaking fast!

 

Its a beast of a server brand new Dell R750, dual 6330, 1Tb memory, 10 x 1.92tb NVME, 2 x 9400-16e talking to 12 x 16tb, 8 x 10tb

 

can work with 128gb mem for the moment, just been without for 2 weeks so keen to get everything set back up! once online ill then start playing with the memory config as i think its a server issue.. while dell shipped the server with all memory populated in the first 8 dimms and dell can "optimised" thats not the actual channel config.. ill change the memory into the channel groups when i get back home in a couple of weeks.. 

 

idrac has been so handy while building haha

 

[Vr2Io]

2 minutes ago, ocexperts said:

Its a beast of a server brand new Dell R750, dual 6330, 1Tb memory, 10 x 1.92tb NVME, 2 x 9400-16e talking to 12 x 16tb, 8 x 10tb

Crazy 👍

 

3 minutes ago, ocexperts said:

as i think its a server issue

Agree