On 5/17/2022 11:56 AM, Stephen Hemminger wrote:
On Tue, 17 May 2022 11:31:36 -0400
Don Wallwork <d...@xsightlabs.com> wrote:
Add support for using hugepages for worker lcore stack memory. The
intent is to improve performance by reducing stack memory related TLB
misses and also by using memory local to the NUMA node of each lcore.
EAL option '--huge-worker-stack [stack-size-in-kbytes]' is added to allow
the feature to be enabled at runtime. If the size is not specified,
the system pthread stack size will be used.
Signed-off-by: Don Wallwork <d...@xsightlabs.com>
Acked-by: Morten Brørup <m...@smartsharesystems.com>
---
This looks great, just thinking a little more about what the impact
of using it would be.
Since the memory region for the stack is never freed, it will cause
complaints from address sanitizer and maybe from valgrind.
One way to workaround that would be to use the lower level allocation
routine to get the memory segments. This would make stacks a multiple
of page size which would not be bad idea anyway.
Plus you could use eal_memalloc_seg_bulk.
The problem with using this API is that it requires allocating page
sized stacks
which would be undesirable in memory constrained environments or when the
huge page size is 1GB.
We looked for a place to free this memory, but could not find any place
in DPDK
where the worker threads are canceled. Obviously the worker threads
have to
be stopped before we can free this memory.
