[orchagent]: Add set batch size option to configure consumer table be…

…havior (sonic-net#234)

- Add flexibility to set pop batch size for consumer table. This parameter
  affects the speed of consuming entries from the database. Use a larger
  number will force the consumer to pop out more entries from the database
  on one SPOP operation.

orchagent/main.cpp

@@ -53,6 +53,9 @@ sai_object_id_t gVirtualRouterId;
 sai_object_id_t gUnderlayIfId;
 MacAddress gMacAddress;
 
+#define DEFAULT_BATCH_SIZE  128
+int gBatchSize = DEFAULT_BATCH_SIZE;
+
 bool gSairedisRecord = true;
 bool gSwssRecord = true;
 ofstream gRecordOfs;
@@ -177,14 +180,15 @@ string getTimestamp()
 
 void usage()
 {
-    cout << "usage: orchagent [-h] [-r record_type] [-d record_location] [-m MAC]" << endl;
+    cout << "usage: orchagent [-h] [-r record_type] [-d record_location] [-b batch_size] [-m MAC]" << endl;
     cout << "    -h: display this message" << endl;
     cout << "    -r record_type: record orchagent logs with type (default 3)" << endl;
     cout << "                    0: do not record logs" << endl;
     cout << "                    1: record SAI call sequence as sairedis*.rec" << endl;
     cout << "                    2: record SwSS task sequence as swss*.rec" << endl;
     cout << "                    3: enable both above two records" << endl;
     cout << "    -d record_location: set record logs folder location (default .)" << endl;
+    cout << "    -b batch_size: set consumer table pop operation batch size (default 128)" << endl;
     cout << "    -m MAC: set switch MAC address" << endl;
 }
 
@@ -199,10 +203,13 @@ int main(int argc, char **argv)
 
     string record_location = ".";
 
-    while ((opt = getopt(argc, argv, "m:r:d:h")) != -1)
+    while ((opt = getopt(argc, argv, "b:m:r:d:h")) != -1)
     {
         switch (opt)
         {
+        case 'b':
+            gBatchSize = atoi(optarg);
+            break;
         case 'm':
             gMacAddress = MacAddress(optarg);
             break;

orchagent/orch.cpp

@@ -10,6 +10,8 @@
 
 using namespace swss;
 
+extern int gBatchSize;
+
 extern mutex gDbMutex;
 extern PortsOrch *gPortsOrch;
 
@@ -21,7 +23,7 @@ extern string getTimestamp();
 Orch::Orch(DBConnector *db, string tableName) :
     m_db(db)
 {
-    Consumer consumer(new ConsumerStateTable(m_db, tableName));
+    Consumer consumer(new ConsumerStateTable(m_db, tableName, gBatchSize));
     m_consumerMap.insert(ConsumerMapPair(tableName, consumer));
 }
 
@@ -30,7 +32,7 @@ Orch::Orch(DBConnector *db, vector<string> &tableNames) :
 {
     for(auto it : tableNames)
     {
-        Consumer consumer(new ConsumerStateTable(m_db, it));
+        Consumer consumer(new ConsumerStateTable(m_db, it, gBatchSize));
         m_consumerMap.insert(ConsumerMapPair(it, consumer));
     }
 }