Memory not release after fbackup finished.

[Florence Lee]

I'm using fbackup command to backup the entire harddisk to DLT8000 Tape Drive. The problem is after finished the fbackup job, the memory still not released. Example : before fbackup the memory utilization is 22%, fbackup running memory utilization 58% and after finished memory utilization still 58%. Please help me if you have any ideas.

Thanks

[Steven Sim Kok Leong]

Hi,

Try using glance, top and lsof to identify the culprit process that is occupying the memory.

Hope this helps. Regards.

Steven Sim Kok Leong
Brainbench MVP for Unix Admin
http://www.brainbench.com

[Florence Lee]

For yr info, I'm using glance plus, measureware and perfview to monitor the fbackup job but there are no fbackup process in the list and memory still not released.

[Frank Slootweg]

Memory is not supposed to be released. HP-UX treats main memory (RAM) like a cache. A good cache is always full. In order to allow small processes to be started quickly, HP-UX keeps memory 'nearly' full. 'Nearly' means that a memory utilization ("Mem Util" in Glance) of 95 to 96% is normal. Percentages of 97 and above indicate too much memory pressure. On the other hand, percentages well below 95 indicate that you have 'too much' memory, i.e. more than is 'ever' needed.

[Praveen Bezawada]

Hi
From glance checks which processes are using more memory.
The metrics to check are RSS in Process report and memory values in Mem report

...BPK...

[Anthony deRito]

The practical and dependable way to determine what a process is using in terms of real memory and virtual memory, is through 'glance'. By using the process resources, you are able to see the RSS (Resident Memory) values and the VSS (Virtual Memory) values. VSS represents the virtual stack size for the process, meaning the requested memory for this process. If this value increases more and more, it demonstrates a memory increase of the process. This increase could be a memory leak.

[Steven Gillard_2]

One possibility: I have seen this type of behaviour caused by the dynamic VXFS inode cache on 11.x. In glance you can see the "system memory" grow to a large amount after a backup of a system with a larger-than-normal number of files.

The solution is to set a limit on this cache with the vx_ninode and vx_noifree parameters. On my systems these are set to:

vx_ninode 8192
vx_noifree 1

By setting a static size on this cache you can control how much memory is allocated to this cache and keep system memory usage under control. You may like to set vx_ninode to a smaller value depending on how much physical memory is in your system - I have 4Gig and my current system memory usage is 254Meg.

Regards,
Steve