This is a temporary solution to ensure that indexes created with w:majority are guaranteed to be usable to a read using majority readConcern level. Currently w:majority only waits for the OpTime and does not wait for the SnapshotName set on the Client. This means that it is possible for an index to be in the committed snapshot but not usable to queries since they are using a too old SnapshotName. The changes for this ticket will be made unnessesary once we complete the work of reunifying OpTime and SnapshotName for SERVER-20439.
Original title: Running count with readConcern majority and a hint errors
Original description:
When running a count with a hint and readConcern majority, the command fails with planner returned bad hint.
Here is the dbCommand object:
{
"count" : "jstests_hint1",
"query" : {
"live" : true,
"ts" : {
"$lt" : ISODate("2009-02-08T18:55:08.272Z")
},
"cls" : "entry",
"verticals" : "alleyinsider"
},
"hint" : {
"ts" : 1
},
"fields" : {
},
"readConcern" : {
"level" : "majority"
}
}
And the log output with the error.
m31000| 2015-09-02T11:14:05.543-0400 I COMMAND [conn1] command test.jstests_hint1 command: count { count: "jstests_hint1", query: { live: true, ts: { $lt: new Date(1234119308272) }, cls: "entry", verticals: "alleyinsider" }, hint: { ts: 1.0 }, fields: {}, readConcern: { level: "majority" } } ntoreturn:1 ntoskip:0 keyUpdates:0 writeConflicts:0 numYields:0 reslen:273 locks:{ Global: { acquireCount: { r: 2 } }, Database: { acquireCount: { r: 1 } }, Collection: { acquireCount: { r: 1 } } } protocol:op_command 1919ms
{
"waitedMS" : NumberLong(945),
"ok" : 0,
"errmsg" : "error processing query: ns=test.jstests_hint1Tree: $and\n cls == \"entry\"\n live == true\n verticals == \"alleyinsider\"\n ts $lt new Date(1234119308272)\nSort: {}\nProj: {}\n planner returned error: bad hint",
"code" : 2
}
- is duplicated by
-
SERVER-20261 Planner unable to find index for $geoNear query with readConcern majority
-
- Closed
-
- related to
-
SERVER-19212 New indexes shouldn't be usable until they are in the committed view
-
- Closed
-
-
SERVER-20439 Use OpTimes as SnapshotNames
-
- Closed
-