Commit 27245e0d authored by Jens Stutte's avatar Jens Stutte
Browse files

Bug 1891936 - Have explicit grace timeout settings for the... 

Bug 1891936 - Have explicit grace timeout settings for the BackgroundEventTarget thread pools. r=KrisWright

Differential Revision: https://phabricator.services.mozilla.com/D209197
parent 43fa6f4f

xpcom/threads/nsThreadManager.cpp

+15 −3
Original line number Diff line number Diff line
@@ -86,13 +86,17 @@ nsresult BackgroundEventTarget::Init() { 
  rv = pool->SetIdleThreadLimit(1);

  NS_ENSURE_SUCCESS(rv, rv);



  // Leave threads alive for up to 5 minutes

  // Leave the base idle thread alive for up to 5 minutes

  rv = pool->SetIdleThreadMaximumTimeout(300000);

  NS_ENSURE_SUCCESS(rv, rv);



  // Leave excess idle threads alive for up to 1 second

  rv = pool->SetIdleThreadGraceTimeout(1000);

  NS_ENSURE_SUCCESS(rv, rv);



  // Initialize the background I/O event target.

  nsCOMPtr<nsIThreadPool> ioPool(new nsThreadPool());

  NS_ENSURE_TRUE(pool, NS_ERROR_FAILURE);

  NS_ENSURE_TRUE(ioPool, NS_ERROR_FAILURE);



  // The io pool spends a lot of its time blocking on io, so we want to offload

  // these jobs on a lower priority if available.
@@ -108,16 +112,24 @@ nsresult BackgroundEventTarget::Init() { 
  NS_ENSURE_SUCCESS(rv, rv);



  // Thread limit of 4 makes deadlock during synchronous dispatch less likely.

  // TODO: This pool is meant to host blocking (file, network) IO, so we might

  // want to configure an even higher limit to allow more parallel operations

  // to find another thread. But first we should audit the existing uses of

  // NS_DISPATCH_EVENT_MAY_BLOCK if they are not just CPU heavy runnables.

  rv = ioPool->SetThreadLimit(4);

  NS_ENSURE_SUCCESS(rv, rv);



  rv = ioPool->SetIdleThreadLimit(1);

  NS_ENSURE_SUCCESS(rv, rv);



  // Leave threads alive for up to 5 minutes

  // Leave allowed idle threads alive for up to 5 minutes

  rv = ioPool->SetIdleThreadMaximumTimeout(300000);

  NS_ENSURE_SUCCESS(rv, rv);



  // Leave excess idle threads alive for up to 500ms seconds

  rv = ioPool->SetIdleThreadGraceTimeout(500);

  NS_ENSURE_SUCCESS(rv, rv);



  pool.swap(mPool);

  ioPool.swap(mIOPool);