Bug 177811 - vm.nr_hugepages not allocating memory after setting to 0
Summary: vm.nr_hugepages not allocating memory after setting to 0
Status: NEW
Alias: None
Product: Other
Classification: Unclassified
Component: Other (show other bugs)
Hardware: x86-64 Linux
: P1 normal
Assignee: other_other
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2016-10-17 09:47 UTC by andrei.grg
Modified: 2016-10-17 09:47 UTC (History)
0 users

See Also:
Kernel Version: 4.7.6
Subsystem:
Regression: No
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Description andrei.grg 2016-10-17 09:47:04 UTC 
Steps to reproduce:

- Use 1GB pagefiles.
- echo 9 > /proc/sys/vm/nr_hugepages
- check that the 9GB memory is now reserved, and it should.
- echo 0 > /proc/sys/vm/nr_hugepages
- check that the 9GB reservation has beed freed, and it should.
- echo 9 > /proc/sys/vm/nr_hugepages
- check that the 9GB memory is reserved, and it's not. (or it reserves less.)

More info: Performing these steps the memory reserved was less and less as 9GB until no reservation was made anymore at all. It can also be the case that after the free-up it allocates only around 1GB and then it stops.
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