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Denis Shcherbakov <deniss@×××××××××.EDU> writes: |
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> Sorry if this question is inappropriate for this forum, but I figure this |
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> is where the experts are :) |
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> |
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> I run Mathematica 5.0 on Gentoo Linux 1.4 (2.4.19-gentoo-r10 kernel) on a |
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> dual-processor machine. I was wondering why my graphic applications came |
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> to a screeching halt when I began running a computation in Mathematica, |
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> and then when I looked at top, my jaw droped - MathKernel is using ALL of |
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> my remaining memory, and I got 2 GB of it on this machine! |
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> |
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> My question is what can I do about this... Is there a way to cap the |
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> amount of memory accessible to Mathematica? Is it possible to put a |
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> quota |
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|
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It sounds like MathKernel uses an over-commit strategy (like what |
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CMUCL and SBCL Common Lisp implementations on GNU/Linux use). They |
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are not really using that much memory. They over-commit in order to |
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have a linear address space in which to implement their own memory |
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management schemes. |
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For example, CMUCL on Gentoo, looks like this in the top(1) output: |
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|
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$ top |
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top - 15:43:40 up 21 days, 5:47, 1 user, load average: 1.03, 0.74, 0.36 |
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Tasks: 111 total, 2 running, 108 sleeping, 0 stopped, 1 zombie |
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Cpu(s): 97.4% us, 2.3% sy, 0.0% ni, 0.0% id, 0.0% wa, 0.3% hi, 0.0% si |
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Mem: 514180k total, 497184k used, 16996k free, 50088k buffers |
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Swap: 1004052k total, 122512k used, 881540k free, 225592k cached |
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|
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PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND |
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22549 mkennedy 25 0 1284m 8244 22m R 1.0 1.6 5:24.32 lisp |
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You should look in the %MEM column for the "real" measure. |
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However, you wrote "graphic applications came to a screeching halt" -- |
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over-committing would not explain that though (presumably very high |
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CPU usage on Mathematica's behalf??). You might want to try Linux |
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2.6.x kernels which provide much improved desktop responsiveness. |
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|
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Matt |
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|
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-- |
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Matthew Kennedy |
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Gentoo Linux Developer |
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