- Community Home
- >
- Servers and Operating Systems
- >
- Integrity Servers
- >
- Re: rx5670 Disk I/O performance problems :(
Categories
Company
Local Language
Forums
Discussions
Forums
- Data Protection and Retention
- Entry Storage Systems
- Legacy
- Midrange and Enterprise Storage
- Storage Networking
- HPE Nimble Storage
Discussions
Discussions
Discussions
Forums
Forums
Discussions
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
- BladeSystem Infrastructure and Application Solutions
- Appliance Servers
- Alpha Servers
- BackOffice Products
- Internet Products
- HPE 9000 and HPE e3000 Servers
- Networking
- Netservers
- Secure OS Software for Linux
- Server Management (Insight Manager 7)
- Windows Server 2003
- Operating System - Tru64 Unix
- ProLiant Deployment and Provisioning
- Linux-Based Community / Regional
- Microsoft System Center Integration
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Community
Resources
Forums
Blogs
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-14-2004 04:36 AM
тАО07-14-2004 04:36 AM
thanks again to everyone who can help.
joe...
Solved! Go to Solution.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-14-2004 04:50 AM
тАО07-14-2004 04:50 AM
Solutiondepending on the locality of the data and the buffering capability of you copy program there will still be a lot of time spent moving the heads between different areas of the disk.
Can you find out about how many reads and writes per second are going to this disk?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-14-2004 05:08 PM
тАО07-14-2004 05:08 PM
Re: rx5670 Disk I/O performance problems :(
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-15-2004 08:50 AM
тАО07-15-2004 08:50 AM
Re: rx5670 Disk I/O performance problems :(
I tried setting the system param to 1 and I didn't notice any gain in performance.
FYI--Here are my copy times:
RAID to DISK: 11 mb/sec
DISK to DISK: 3 mb/sec
DISK to RAID: 3 mb/sec
RAID to RAID: 3 mb/sec
Unforunately, most of the time I'm doing RAID to RAID copies.
Also, here is my FSTAB file:
/dev/vg00/lvol3 / vxfs delaylog 0 1
/dev/vg00/lvol1 /stand vxfs tranflush 0 1
/dev/vg00/lvol4 /tmp vxfs delaylog 0 2
/dev/vg00/lvol5 /home vxfs delaylog 0 2
/dev/vg00/lvol6 /opt vxfs delaylog 0 2
/dev/vg00/lvol7 /usr vxfs delaylog 0 2
/dev/vg00/lvol8 /var vxfs delaylog 0 2
/dev/vg01/lvol9 /usr/local/banner vxfs delaylog 0 2
/dev/vg02/lvol10 /usr/local/banner/oradata vxfs rw,largefiles,delaylog 0 2
vol10 = eXTERNAL RAID 12/h
vol9 = Internal Disk
joe...
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-15-2004 09:34 AM
тАО07-15-2004 09:34 AM
Re: rx5670 Disk I/O performance problems :(
So, once the small cache (96MB) was filled, you would be limited to the performance of the back end. If you get close to filling the disk, you will be moving things to RAID 5 and be incurring the RAID 5 write penalty.
Reading from the array and writing to your internal disk is the best because read come in on one bus and go out on another, and there is no thrashing of the disk heads from seeks back and forth between reading and writing. You can test performance using dd from /dev/zero to a file or from a file to /dev/null. Use a large block size so that you aren't seeing the effects of file system overhead as much. I you create some lvols with different mount options, you can get an idea of the file system overhead with those mount options. I hope this helps, but copying from one device to the same device is always going to be slow unless you have a large block size and don't journal the file system. You can use sam to set some of the mount options. Some are only available with OnLineJFS, which I would recommend.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-19-2004 10:19 AM
тАО07-19-2004 10:19 AM
Re: rx5670 Disk I/O performance problems :(
joe...
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-19-2004 01:39 PM
тАО07-19-2004 01:39 PM
Re: rx5670 Disk I/O performance problems :(
How much RAM is in your system? What is the value of bufpages, dbc_max_pct and dbc_min_pct?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-20-2004 02:40 AM
тАО07-20-2004 02:40 AM
Re: rx5670 Disk I/O performance problems :(
max=8
min=5
bufpages=0
As for the transfer rates:
from vg01 -> vg00 11 mb/sec
from vg00 -> vg01 10 mb/sec
From what I understand, I should be getting a max trasnfer rate of 20 mb/sec.
thanks again and I hope this information helps!
joe...
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-20-2004 02:41 AM
тАО07-20-2004 02:41 AM
Re: rx5670 Disk I/O performance problems :(
joe...
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО07-20-2004 03:30 AM
тАО07-20-2004 03:30 AM
Re: rx5670 Disk I/O performance problems :(
Do you have performance issues in vg02? If so, what type of drives are they? Are most of your disk I/Os really sequential or are they random. Please not that when you are reading and writing to the same physical disk, you are likely limited by the track to track switching time. Your expectation of 1GB per minute (~16MB/sec) when copying from and to the same drive is unrealistic even on the latest disk drives on the fastest buses today. Too much time is spend moving the heads to and from the read and write areas. Naturally, there are different ways to make the copy algorithm more efficient in a specific case, but you can test the one-way performance copying or dd'ing a file to /dev/null or dd'ing from /dev/zero to a file.