setFCV to 4.4 should insert range deletion tasks in batches rather than one at a time

(function() {

'use strict';

// Skip checking orphans because it takes a long time when there are so many chunks. Also we don't

// actually insert any data so there can't be orphans.

TestData.skipCheckOrphans = true;

const dbName = "db1";

const collName = "foo";

const ns = dbName + "." + collName;

const st = new ShardingTest({

    shards: 2,

    config: 1,

    other: {

// How to run this test with a specific binary version.

//      mongosOptions: {binVersion: "4.4"},

//      shardOptions: {binVersion: "4.4"},

//      configOptions: {binVersion: "4.4"},

    }

});

jsTest.log("Set FCV to 4.2 since we want to test upgrading the FCV to 4.4");

assert.commandWorked(st.s.adminCommand({ setFeatureCompatibilityVersion: "4.2" }));

jsTest.log("Create a database.");

// enableSharding creates the databases.

assert.commandWorked(st.s.adminCommand({enableSharding: dbName}));

st.ensurePrimaryShard(dbName, st.shard0.shardName);

jsTest.log("Shard a collection with a huge number of initial chunks");

const NUM_CHUNKS = 100000;

assert.commandWorked(st.s.adminCommand({ shardCollection: ns, key: {x: "hashed"}, numInitialChunks: NUM_CHUNKS }));

assert.gt(st.s.getDB("config").chunks.count(), NUM_CHUNKS - 1);

jsTest.log("Set FCV to 4.4");

assert.commandWorked(st.s.adminCommand({ setFeatureCompatibilityVersion: "4.4" }));

st.stop();

})();

diff --git a/src/mongo/db/s/config/configsvr_shard_collection_command.cpp b/src/mongo/db/s/config/configsvr_shard_collection_command.cpp

index 68af077751..9f37b7da94 100644

--- a/src/mongo/db/s/config/configsvr_shard_collection_command.cpp

+++ b/src/mongo/db/s/config/configsvr_shard_collection_command.cpp

@@ -107,7 +107,7 @@ void validateAndDeduceFullRequestOptions(OperationContext* opCtx,

     // Cannot have more than 8192 initial chunks per shard. Setting a maximum of 1,000,000

     // chunks in total to limit the amount of memory this command consumes so there is less

     // danger of an OOM error.

-    const int maxNumInitialChunksForShards = numShards * 8192;

+    /*const int maxNumInitialChunksForShards = numShards * 8192;

     const int maxNumInitialChunksTotal = 1000 * 1000;  // Arbitrary limit to memory consumption

     int numChunks = request->getNumInitialChunks();

     uassert(ErrorCodes::InvalidOptions,

@@ -116,7 +116,7 @@ void validateAndDeduceFullRequestOptions(OperationContext* opCtx,

                           << maxNumInitialChunksTotal,

             numChunks >= 0 && numChunks <= maxNumInitialChunksForShards &&

                 numChunks <= maxNumInitialChunksTotal);

-

+    */

     // Retrieve the collection metadata in order to verify that it is legal to shard this

     // collection.

     BSONObj res;

diff --git a/src/mongo/db/s/config/initial_split_policy.cpp b/src/mongo/db/s/config/initial_split_policy.cpp

index 1af9ceb57f..dfb054f4fa 100644

--- a/src/mongo/db/s/config/initial_split_policy.cpp

+++ b/src/mongo/db/s/config/initial_split_policy.cpp

@@ -193,7 +193,7 @@ InitialSplitPolicy::ShardCollectionConfig InitialSplitPolicy::generateShardColle

         // shards, and we need to be sure that at least one chunk is placed on the primary shard

         const ShardId shardId = (i == 0 && finalSplitPoints.size() + 1 < allShardIds.size())

             ? databasePrimaryShardId

-            : allShardIds[(i / numContiguousChunksPerShard) % allShardIds.size()];

+            : allShardIds[(i / 1 /*numContiguousChunksPerShard*/) % allShardIds.size()];         appendChunk(nss, min, max, &version, validAfter, shardId, &chunks);

     }

void myFunc() {

    Timer t;

    // do something time-consuming

    auto micros = t.micros();

    LOGV2(123456, "How long it took", "micros"_attr = micros);

}