Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations strongm on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

EMC CX200 & Emulex LP982 HBA Bandwidth Problem

Status
Not open for further replies.

srinibee

Vendor
Aug 22, 2003
48
US
Hi all,

I have a EMC CX200 with 10x36GB 10K RPM drives. I have configured the array in RAID3 and an element size set to 2blocks as per my clients requirement. My client requires only RAID3 since he is working on Realtime data capture applications. The host is a REDHAT LINUX 7.3 Professional and kernel version is 2.4.18-3smp. We have installed the Emulex LP982 2Gbps HBA card. Infact EMC has suggested Qlogic2340 HBA. If I compare both the Qlogic and Emulex there is no much difference. EMC has certified the Emulex LP982 card for above LINUX version and the kernel version as well.

My problem starts here: Presently I am getting 48MB/s bandwidth. I have to demonstrate atleast 80MB/s to my customer with the above configuration. Unfortunately EMC could not give any fine tuning parameters to increase the Bandwidth to 80MB/s. I have set the following parameters in the HBA driver and recompiled the kernel and there is no use.

Can somebody shed some light to come out of this issue?

PLEASE.....!!!!!

regards
Srinivas Bandaru
email: srineeb@tataelxsi.co.in
 
What type of machine are you using? Model/Make/Bus Speeds/Bus the Emulex Card is in?

You can only move data as fast as the slowest component on your system.
 
Thanks for the immediate response. Here is my config:
HP ML530 with 2x2.8GHz Xeon processors
533MHz front size BUS.
133MHz PCI-X BUS. The emulex HBA is on PCI-X 133MHz slot.

regards
Srinivas Bandaru
 
What is the end to end solution? Are you using a switched environment or point-to-point? If you are using a switched environment make sure your HBA is not set to Auto-Negotiate as well as the switch port.
 
Hi,

Its a DAS. (Direct Attach).

regards
Srinivas Bandaru
 
Can you send me the specs of your host machine?

What is the Make and Model of your host?

I am going to run this through an EMC configurator.
 
I have got a configurator doc from EMC. Unfortunately the procedure is for Qlogic 2340 HBA. I need a configurator for Emulex LP982E HBA and Redhat Linux 7.3 professional and kernel 2.4.18_3smp.

Here is my HOST config:
1. HP ML530 with 2x2.8GHz Xeon processors
2. 533MHz front size BUS.
3. 133MHz PCI-X BUS. The emulex HBA is on PCI-X 133MHz slot

4. Redhat Linux 7.3 Professional running on
2.4.18_3smp kernel.
5. Driver ver for Emulex LP982E HBA= 4.20q (suggested by
EMC/Emulex)
6. Firmware ver for Emulex LP982E HBA = 100a4
7. 36GB 10K RPM drives.
8. 8+1+1 RAID3.
9. Element size = 2blocks.
10. EXT2 Filesystem on LINUX. (default blocksize=4096)

I am using a customized benchmark program to test. The benchmark program was provided by the customer to test. I have tested using my own benchmark program as well.

I can send you the benchmark program to you if u want.
How do I enable writeback or writethru cache on the array???

U are the only one to respond. Pl help me!!!!!!!!!!!.

regards
Srinivas Bandaru
 
I know you do not want to hear this but I am going to state it anyway.

EMC does not support your version of Linux using an Emulex HBA with the CX200. I have verified this through the EMC partner page, EMC Compatibility Docs, and the ESN configurator.

Yes, Emulex does have an EMC driver for the LP982 for Redhat that is not supported any longer.

The latest driver for Redhat from Emulex is version 4.21g for the following but it is not an EMC driver;
32-bit Intel Architecture:
Red Hat Linux 7.3 (x86) with 2.4.18-27 kernel
Red Hat Linux 8.0 (x86) with 2.4.18-27 kernel

Firmware - 1.01a2


Emulex no longer has your version on their support list for EMC as well.

I strongly suggest you what is suggested by the EMC compatibility matrix for maximum performance.

The worst thing about these solutions is keeping up with what is supported by each vendor.

Sorry I cannot help you with what your current issue is, but if you use the supported configuration you should see better results.
 
My sincere thanks to comtek. The fact is like this, I have downloaded the 4.20g driver and 100a4 firmware for Linux 7.3 kernel 2.4.18-3smp last week from Emulex Site under EMC support page. Unfortunately the Linux content on the page were missing since then I had escalated the problem to Emulex/EMC. Looks like after escalating the problem Emulex/EMC tested the setup and withdrawn the support for LP982 HBA.
I will try the 4.21q and update the firmware as well. I will install the 2.4.18-27smp kernel as well.

Can pl tell me the link from where I can download the 2.4.18-27smp kernel. I have tried several sites.

regards
Srinivas Bandaru
 
Thanks to everybody for their support. Finally we have achieved.

We have replaced all Emulex LP982 HBA's with Qlogic QLA2340-CK. upgraded the firmware for all the qla cards and we go the good bandwidth of 100MB/s

regards
Srinivas Bandaru
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top