[pypy-svn] r58544 - pypy/build/doc

[xoraxax at codespeak.net]

Author: xoraxax
Date: Thu Oct  2 00:10:09 2008
New Revision: 58544

Modified:
   pypy/build/doc/benchmark_memory.txt
Log:
My ideas and new tools/urls -- mackall provides a linux patchset for better page mapping info, exmap provides interesting information.

Modified: pypy/build/doc/benchmark_memory.txt
==============================================================================
--- pypy/build/doc/benchmark_memory.txt	(original)
+++ pypy/build/doc/benchmark_memory.txt	Thu Oct  2 00:10:09 2008
@@ -113,6 +113,12 @@
 swapping.  When Y and Z agree, we found a good way to measure
 memory usage.
 
+  xoraxax: doesnt that depend a lot of the runtime memory accesses of the
+  other processes and reproducible algorithms in the VM wrt. paging
+  decisions? E.g. in one scenario the VM could decide to page out
+  data to the swapfile while in another case it could just unmap
+  .text pages
+
 Understanding linux /proc/pid/smaps info
 -------------------------------------------
 
@@ -289,3 +295,12 @@
 
 XXX discuss and write toolchain
 
+Exmap can be used to see very useful statistics about processes
+including very precise shared RSS figures. It can also show
+whether a specific symbol is mapped into the RAM but this
+does not seem to be precise in xorAxAx's tests as the information
+seems to be invariant to e.g. the usage of unicodedata.
+
+http://lwn.net/Articles/230975/ presents some ideas and a set
+of patches for more precise page mapping information by
+matt mackall