Loading...
Loading...
In three additional cases (beyond the ones described in SERVER-35479 and SERVER-35522) the results of collStats depends on the topology of the server. Currently, if one attaches to a standalone instance of mongo, one will receive the NamespaceNotFound error code if one asks for collStats with the queryExecStats or storageStats options on a namespace that doesn't exist (e.g. "dne"). Additionally, one will receive a numeric error code if one passes an unknown option (e.g. "unknown"). However, if one connects to a mongos the NamespaceNotFound errors will be suppressed by the mongos instance if one pass such options to a namespace that doesn't exist. Additionally, because we don't validate that the options passed to collStats are correct when we do a "light parse" of the pipeline we actually get a NamespaceNotFound error when we get the routing info which then gets suppressed by the same code path if one asks for collStats on a collection that doesn't exist with an unknown option. Resolution of this ticket should include: 1) Stopping mongos from suppressing namespace not found errors. 2) Ensuring that mongos produces an option validation error before a namespace not found error in the event of unknown options being passed to a collStats stage being run on a nonexistent namespace. 3) Tests to verify that collStats behaves correctly regardless of topology.
xgen-internal-githook commented on Tue, 23 Mar 2021 00:54:24 +0000: Author: {'name': 'ruslan.abdulkhalikov', 'email': 'ruslan.abdulkhalikov@mongodb.com', 'username': 'rusabd1'} Message: SERVER-53083 collStats results depend on topology and option Branch: master https://github.com/mongodb/mongo/commit/20c01a9f4cd201662f9d67f3974fd85df0979186 JIRAUSER1258164 commented on Thu, 7 Jan 2021 19:05:07 +0000: Still trying to get my first build. But sure! via [1]Newton Mail On Thu, Jan 7, 2021 at 10:49 AM, Charlie Swanson (Jira) wrote: Message Title [2]Charlie Swanson assigned an issue to [3]Joel Redman [4]Joel Redman I'm assigning this to you to track for the next sprint. Please take a look after you get to a good stopping point and/or blocked with your current ticket. [5]Core Server / [6][7]SERVER-53083 [8]collStats results depend on topology and option. Change By: [9]Charlie Swanson Sprint: Query 2020-12-28, Query 2021-01- 11 25 Assignee: Backlog - Query Optimization Joel Redman [10] [11]Add Comment This message was sent from MongoDB's issue tracking system. To respond to this ticket, please login to [12]jira.mongodb.org using your JIRA, MongoDB Cloud Manager, or MongoDB Atlas credentials. ---------------------------------------------------------------------------------------- [1] https://cloudmagic.com/k/d/mailapp?ct=pi&cv=10.0.53&pv=14.2&source=email_footer_2 [2] https://jira.mongodb.org/secure/ViewProfile.jspa?name=charlie.swanson [3] https://jira.mongodb.org/secure/ViewProfile.jspa?name=joel.redman [4] https://jira.mongodb.org/secure/ViewProfile.jspa?name=joel.redman [5] https://jira.mongodb.org/browse/SERVER [6] https://jira.mongodb.org/browse/SERVER-53083 [7] https://jira.mongodb.org/browse/SERVER-53083 [8] https://jira.mongodb.org/browse/SERVER-53083 [9] https://jira.mongodb.org/secure/ViewProfile.jspa?name=charlie.swanson [10] https://jira.mongodb.org/browse/SERVER-53083#add-comment [11] https://jira.mongodb.org/browse/SERVER-53083#add-comment [12] https://jira.mongodb.org charlie.swanson commented on Thu, 7 Jan 2021 18:48:58 +0000: joel.redman I'm assigning this to you to track for the next sprint. Please take a look after you get to a good stopping point and/or blocked with your current ticket.
1) Setup a mongod instance. 2) Connect to the mongod instance and run the following commands producing the following output: > db.runCommand({aggregate: "dne", pipeline:[{"$collStats": {"unknown": {}}}], cursor:{}}) { "ok" : 0, "errmsg" : "unrecognized option to $collStats: unknown", "code" : 40168, "codeName" : "Location40168" } > db.runCommand({aggregate: "dne", pipeline:[{"$collStats": {"queryExecStats": {}}}], cursor:{}}) { "ok" : 0, "errmsg" : "PlanExecutor error during aggregation :: caused by :: Unable to retrieve queryExecStats in $collStats stage :: caused by :: Collection [test.dne] not found.", "code" : 26, "codeName" : "NamespaceNotFound" } > db.runCommand({aggregate: "dne", pipeline:[{"$collStats": {"storageStats": {}}}], cursor:{}}) { "ok" : 0, "errmsg" : "PlanExecutor error during aggregation :: caused by :: Unable to retrieve storageStats in $collStats stage :: caused by :: Collection [test.dne] not found.", "code" : 26, "codeName" : "NamespaceNotFound" } 3) Start a sharded cluster (e.g. by running let st = ShardingTest({shards: 2}) in the mongo shell with the `--nodb` option). 4) Connect to the mongos and run the following commands producing the following results: (if you use `ShardingTest` to start the sharded cluster the mongos should be on port 20005) mongos> db.runCommand({aggregate: "dne", pipeline:[{"$collStats": {"unknown": {}}}], cursor:{}}) { "result" : [ ], "cursor" : { "id" : NumberLong(0), "ns" : "test.dne", "firstBatch" : [ ] }, "ok" : 1, "$clusterTime" : { "clusterTime" : Timestamp(1606339832, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } }, "operationTime" : Timestamp(1606339832, 1) } mongos> db.runCommand({aggregate: "dne", pipeline:[{"$collStats": {"queryExecStats": {}}}], cursor:{}}) { "result" : [ ], "cursor" : { "id" : NumberLong(0), "ns" : "test.dne", "firstBatch" : [ ] }, "ok" : 1, "$clusterTime" : { "clusterTime" : Timestamp(1606339835, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } }, "operationTime" : Timestamp(1606339835, 1) } mongos> db.runCommand({aggregate: "dne", pipeline:[{"$collStats": {"storageStats": {}}}], cursor:{}}) { "result" : [ ], "cursor" : { "id" : NumberLong(0), "ns" : "test.dne", "firstBatch" : [ ] }, "ok" : 1, "$clusterTime" : { "clusterTime" : Timestamp(1606339835, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } }, "operationTime" : Timestamp(1606339835, 1) }
Click on a version to see all relevant bugs
MongoDB Integration
Learn more about where this data comes from
Bug Scrub Advisor
Streamline upgrades with automated vendor bug scrubs
BugZero Enterprise
Wish you caught this bug sooner? Get proactive today.