Changeset 1200

Timestamp:

07/07/17 15:52:44 (7 years ago)

Author:

rlacroix

Message:

Improve the buffer size estimation.

This in fact reverts r1190 but with an improved version of the old code to avoid mispredicting the maximum number of bufferable events.

Also add comments so that I don't remove that code again in 6 months...

File:

• XIOS/trunk/src/node/context.cpp (modified) (4 diffs)

XIOS/trunk/src/node/context.cpp

@@ -268 +268 @@
    void CContext::setClientServerBuffer()
    {
-     size_t minBufferSize = CXios::minBufferSize;
+     // Estimated minimum event size for small events (10 is an arbitrary constant just for safety)
+     const size_t minEventSize = CEventClient::headerSize + getIdServer().size() + 10 * sizeof(int);
+     // Ensure there is at least some room for 20 of such events in the buffers
+     size_t minBufferSize = std::max(CXios::minBufferSize, 20 * minEventSize);
 #define DECLARE_NODE(Name_, name_)    \
      if (minBufferSize < sizeof(C##Name_##Definition)) minBufferSize = sizeof(C##Name_##Definition);
@@ -276 +279 @@
 #undef DECLARE_NODE_PAR
 
+     // Compute the buffer sizes needed to send the attributes and data corresponding to fields
      std::map<int, StdSize> maxEventSize;
      std::map<int, StdSize> bufferSize = getAttributesBufferSize(maxEventSize);
@@ -284 +288 @@
        if (it->second > bufferSize[it->first]) bufferSize[it->first] = it->second;
 
+     // Apply the buffer size factor and check that we are above the minimum buffer size
      ite = bufferSize.end();
      for (it = bufferSize.begin(); it != ite; ++it)
@@ -289 +294 @@
        it->second *= CXios::bufferSizeFactor;
        if (it->second < minBufferSize) it->second = minBufferSize;
+     }
+
+     // Leaders will have to send some control events so ensure there is some room for those in the buffers
+     if (client->isServerLeader())
+     {
+       const std::list<int>& ranks = client->getRanksServerLeader();
+       for (std::list<int>::const_iterator itRank = ranks.begin(), itRankEnd = ranks.end(); itRank != itRankEnd; ++itRank)
+       {
+         if (!bufferSize.count(*itRank))
+         {
+           bufferSize[*itRank] = minBufferSize;
+           maxEventSize[*itRank] = minEventSize;
+         }
+       }
      }