Android cannot create mmap'ed file in /tmp, so only use it if 'zerocopy' set

[bmah888]

From frode.isaksen on November 27, 2013 07:11:25

Android cannot create mmap'ed file in /tmp, so only use it if 'zerocopy' set. If not 'zerocopy', use malloc'ed buffer instead of mmap'ed buffer.
Patch attached.

Attachment: android-fix.diff

Original issue: http://code.google.com/p/iperf/issues/detail?id=116

[bmah888]

From jef.poskanzer on December 13, 2013 08:43:40

There's some similar code in issue 100 's patches.

There's also similar code to be found in old versions of iperf_api.c. The first mmap version was 324, so this will get you the final malloc version:
hg cat -r 323 src/iperf_api.c
It does at least one thing this patch does not: page-align the buffer. So that idea should be combined with the patch's conditional mmap/malloc.

[bmah888]

From jef.poskanzer on December 13, 2013 08:47:20

Actually, on second glance what the patch in issue 100 does is use /cache instead of /tmp on Android. If that makes it possible to continue using mmap in all cases then that is the simpler change and we don't need to resurrect the malloc code.

[bmah888]

From frode.isaksen on December 13, 2013 08:54:37

We would like to use a single binary for both Android and Linux, so having a conditional compile flag for Android is not that good..
What about passing the location for the mmap'ed buffer as a parameter (while keeping /tmp as default) ?
Also, I can rework the patch to page-align the buffer if you want.

[bmah888]

From jef.poskanzer on December 13, 2013 09:36:37

Not needing to build a separate Android binary is a good goal, but --zerocopy functioning on Android is even better.

Maybe there's some way to do a runtime test of whether to use /tmp or /cache.

[bmah888]

From frode.isaksen on December 17, 2013 05:13:29

OK - if using /tmp fails, I will try using /cache. Is this OK or ??

[bmah888]

From bltierney@es.net on December 18, 2013 13:43:43

Labels: Milestone-3.1a1

[bmah888]

From frode.isaksen on January 17, 2014 01:07:59

Included you will find a patch that will try different locations for the temporary mmap'ed file. I have added /cache for Android, but you can easily add other locations as well.

Attachment: android-fix2.diff

[bmah888]

As a part of #517, iperf3 (as of about 3.2) now honors the $TMPDIR environment variable, so I think that should solve this problem. (This was also mentioned in pull request #313). Closing this issue.