memory limit per process with chatr +q3p enable

[Yuan Qu]

I searched the solutions on increasing the memory limit per process for 32 bit application on hp11.11.

Here's several options
1) compiled with -Wl,-N for aCC
2) chatr +q3p enable a.out
3) chatr +q4p enable a.out

I had a small program basically malloc memories.
Without any option above, it run out of memory around 895M.
If I use option (1), it can get to 1023M.
With option (2), it can get to 1022M.
If I use both (1) and (2), it gets to 1022M.
With option (3), it gets to 1788M.

It can't get 3GB memory utilization per process, what could be wrong here?

Thanks,
Yqu

[Stefan Farrelly]

Have you checked the requirements;

1. Enough RAM (3.8Gb free which is the max with q4 enabled)
2. Enough device swap (at least 3.8Gb) - and it all free (0% used)
3. maxdsiz set to at lest 3.8GB in the kernel

I thought q3 and q4 are shared quadrants, so its possible already running processes are using part of them, limiting your usage. Have you tried running your program in single user mode when nobody else could be accessing them?

[Yuan Qu]

maxdsiz 786432 maxssiz 32768 maxswapchunks 3080
swchunk 2048

There are 5 GB left for swapspace.

I am not sure if any process is using the shared memory. Here's output for ipcs:
Shared Memory:
m 0 0x411c05cc --rw-rw-rw- root root
m 1 0x4e0c0002 --rw-rw-rw- root root
m 2 0x41200015 --rw-rw-rw- root root
m 3 0x301c3ea4 --rw-rw-rw- root root
m 4 0x00000000 --rw------- root root
m 2005 0x431c480b --rw-rw-rw- daemon daemon

are the quadrant 3 and 4 used?

Thanks,
Yqu

[Yuan Qu]

output from swapinfo,
Kb Kb Kb PCT START/ Kb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 6144000 875020 5268980 14% 0 - 1 /dev/vg00/lvol2
reserve - 730156 -730156
memory 1568732 762280 806452 49%

is the memory the problem? I thought the virtual memory would count.

[Stefan Farrelly]

Yes, youre out of memory. The fact the the USED column from DEVICE swap is > 0 (800 odd Megabytes) means you are out of RAM and already 800Mb of RAM has been swapped/paged to disk ! No wonder you cant run your program over 1Gb.

You need to have 3-4Gb of free RAM before you try running your program. Use vmstat 1 1 (look for memory free column, multiply it by 4096 for free ram in bytes)