[3/3] doc: add NB stack comment to EAL "known issues"

Message ID 20190110205538.24435-4-gage.eads@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series Add non-blocking stack mempool handler |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation fail Compilation issues

Commit Message

Eads, Gage Jan. 10, 2019, 8:55 p.m. UTC
  This comment makes users aware of the non-blocking stack option and its
caveats.

Signed-off-by: Gage Eads <gage.eads@intel.com>
---
 doc/guides/prog_guide/env_abstraction_layer.rst | 5 +++++
 1 file changed, 5 insertions(+)
  

Patch

diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst b/doc/guides/prog_guide/env_abstraction_layer.rst
index 929d76dba..9497b879c 100644
--- a/doc/guides/prog_guide/env_abstraction_layer.rst
+++ b/doc/guides/prog_guide/env_abstraction_layer.rst
@@ -541,6 +541,11 @@  Known Issues
 
   5. It MUST not be used by multi-producer/consumer pthreads, whose scheduling policies are SCHED_FIFO or SCHED_RR.
 
+  Alternatively, x86_64 applications can use the non-blocking stack mempool handler. When considering this handler, note that:
+
+  - it is limited to the x86_64 platform, because it uses an instruction (16-byte compare-and-swap) that is not available on other platforms.
+  - it has worse average-case performance than the non-preemptive rte_ring, but software caching (e.g. the mempool cache) can mitigate this by reducing the number of handler operations.
+
 + rte_timer
 
   Running  ``rte_timer_manage()`` on a non-EAL pthread is not allowed. However, resetting/stopping the timer from a non-EAL pthread is allowed.