- Community Home
- >
- Servers and Operating Systems
- >
- Operating Systems
- >
- Operating System - HP-UX
- >
- Memory bus throughput
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
тАО04-13-2005 07:02 PM
тАО04-13-2005 07:02 PM
Is there any method to find out the current memory bus loading. Something like "sar -b" or "sar -d" for buffer cache or block devices.
I have the rp7400 with 6GB of RAM installed, the 2 memory extenders inside;
HP-UX 11.0;
The oracle's database is small enough to reside in the RAM entirely, so no swapping, no disk activity occurs. But sometimes strange delays happens.
Thanks.
Solved! Go to Solution.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-13-2005 07:09 PM
тАО04-13-2005 07:09 PM
Re: Memory bus throughput
use ths command:
# vmstat 3 10
which reports virtual memory statistics of 10 3-secs interval.
man vmstat for more info.
regards.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-13-2005 07:51 PM
тАО04-13-2005 07:51 PM
Re: Memory bus throughput
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-13-2005 08:08 PM
тАО04-13-2005 08:08 PM
Re: Memory bus throughput
for vmstat, the free column shows the free virtual memory in your server. virtual memory is about 4 times less than the physical memory.
you may also use top command, where for Memory section, there is a free field which shows free physical memory.
regards.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-13-2005 08:12 PM
тАО04-13-2005 08:12 PM
Re: Memory bus throughput
//tommy
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-13-2005 08:48 PM
тАО04-13-2005 08:48 PM
Re: Memory bus throughput
So, as I know the pi/po numbers illustrate the swapping activity, and as I wrote above it is absent (in my situation all page counters are zeros). The "avm" colomn demonstrates the number of active memory pages and as I understand has no concern to my question.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-13-2005 08:51 PM
тАО04-13-2005 08:51 PM
Re: Memory bus throughput
or very close to them.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-15-2005 05:49 AM
тАО04-15-2005 05:49 AM
SolutionThere is an unsupported utility called "pi" that will retrieve CPU performance statistics. One of those gives the utilization of the bus to which the CPU is connected. That will also be the "memory" bus utilization on simpler systems, however, an rp7400 is a slightly more complicated machine - it actually has two memory busses, and depending on how you've loaded the CPUs each CPU will be on one, or the other.
So, if you happen to know which CPUs are on which bus, the "sysbus" metric/test from pi will give some idea of the memory bus loading. One systems with heirarchical memory systems (eg 'Domes and rp7410 and rp8XXX) the sysbus will not be quite as useful since it will not give visibility to the other busses.
It would be good to have a system block diagram handy while you do this :)
One other thing - as memory busses become saturated, cache misses take longer and longer to satisfy. That means CPUs sit "idle" longer and longer - however this "idle" is not "idle CPU" as in vmstat/top/glance - it actually shows-up as used CPU - the CPU isn't really "idle" but "stalled"
When you migrate to Itanium, some of the stuff you can do with the unsupported pi utility can be done with the Caliper tool. I'm reasonably certain though that Caliper only reports metrics from the Itanium2 PMU - Performance Management Unit and not from other parts of the CEC (Core Electronics Chipset - aka the "glue") Again, on simpler systems, the CPU memory bus loading _is_ the memory bus loading (rx[1245]XXX systems), and it will be the local memory bus loading for the cell-based systems (rx[78]XXX and 'dome) and again, best to have a system block diagram handy :)
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-15-2005 01:31 PM
тАО04-15-2005 01:31 PM
Re: Memory bus throughput
If your DBA has left out important indexes thinking that serial reads will be just as fast as indexed reads because every is in memory, suggest an Oracle performance class for the DBA to take. If sar reports that there are truly no signifcant disk accesses, then troubleshoot the delays by creating a reprodicbile query or transaction, then use Glance to look at the memory stats (top, vmstat, sar are useless for this task). If you see a high page fault rate (refers to the TLB hardware cache), you can enable large page size for the Oracle engine so that large amounts of memory can be accessed without a TLB miss. Show your DBA/programmers this page:
http://docs.hp.com/en/B2355-90655/ch08s02.html
Bill Hassell, sysadmin
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-15-2005 04:05 PM
тАО04-15-2005 04:05 PM