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Type:
Question
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Resolution: Done
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Priority:
Major - P3
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None
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Affects Version/s: 3.0.3
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Component/s: WiredTiger, Write Ops
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Labels:None
Hi Team ,
There is a performance issue with write operations , data insert to the database very slow in a sudden and will get back to normal in some seconds .
Strange Logs like this :
2015-06-16T10:23:58.212+0800 I COMMAND [conn287864] command ISH_Fact.$cmd command: insert { insert: "FactAppLoginLog", ordered: true, documents: [ { _id: ObjectId('557f88bda310a27a4f3893eb'), userid: "557f5befa310c0e3f3324e2d", username: "15026835043", passauthtime: 578, locationinfo: { height: 0.0, precision: 43.0, gps: [ 31.21235656738281, 121.4836959838867 ] }, ispass: true, uuid: "58a41e3c-2392-3e97-be73-0a4542c3ff0f", os: "Android", type: "PAD", version: "9", eventtime: new Date(1434421366267), eventt: 6, ct: new Date(1434421437738) } ] } keyUpdates:0 writeConflicts:0 numYields:0 reslen:80 locks:{ Global: { acquireCount: { w: 3 } }, Database: { acquireCount: { w: 3 } }, Collection: { acquireCount: { w: 2 } }, oplog: { acquireCount: { w: 1 } } } 474ms
2015-06-16T10:23:58.213+0800 I COMMAND [conn287789] command ISH_Fact.$cmd command: insert { insert: "FactPortalADPresent", ordered: true, documents: [ { _id: ObjectId('557f88bda310a27a4f3893ef'), spotid: "new_ishmobile_rotate_B03", batchid: "9aa09df5-4929-8bfc-13af-556fbe1dd41c", os: "iOS 7", type: "Smartphone", op: "telecom", buv: "14dfa2e18f0-067523f0-e621-4f96-8df9-39e78e4ba0c7", un: "13501880398", site: "i-shanghai", et: new Date(1434421437899) } ] } keyUpdates:0 writeConflicts:0 numYields:0 reslen:80 locks:{ Global: { acquireCount: { w: 3 } }, Database: { acquireCount: { w: 3 } }, Collection: { acquireCount: { w: 2 } }, oplog: { acquireCount: { w: 1 } } } 290ms
As you can see , the op only locks the db for 2 or 3 ms but it cost 300ms to finish , there is only _id index on those tables , about 4,000 write ops every minute on those tables.
Could you advise how to trouble shooting the issue ?
Thanks,
Carl Dong
