On 09-Jan-20 1:27 PM, Olivier Matz wrote:
When allocating a mempool which is larger than the largest available area, it can take a lot of time:a- the mempool calculate the required memory size, and tries to allocate it, it fails b- then it tries to allocate the largest available area (this does not request new huge pages) c- add this zone to the mempool, this triggers the allocation of a mem hdr, which request a new huge page d- back to a- until mempool is populated or until there is no more memory This can take a lot of time to finally fail (several minutes): in step a- it takes all available hugepages on the system, then release them after it fails. The problem appeared with commit eba11e364614 ("mempool: reduce wasted space on populate"), because smaller chunks are now allowed. Previously, it had to be at least one page size, which is not the case in step b-. To fix this, implement our own way to allocate the largest available area instead of using the feature from memzone: if an allocation fails, try to divide the size by 2 and retry. When the requested size falls below min_chunk_size, stop and return an error. Fixes: eba11e364614 ("mempool: reduce wasted space on populate") Cc: sta...@dpdk.org Signed-off-by: Olivier Matz <olivier.m...@6wind.com> ---
I don't particularly like the idea of working around this issue as opposed to fixing it memzone-side, but since there's currently no plan to address this in memzone allocator, this should work much better than before.
Acked-by: Anatoly Burakov <anatoly.bura...@intel.com> -- Thanks, Anatoly
