[SERVER-1124] expose when fsync() happens in db.serverStatus() Created: 14/May/10  Updated: 29/May/12  Resolved: 24/May/10

Status: Closed
Project: Core Server
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: New Feature Priority: Major - P3
Reporter: Kenny Gorman Assignee: Mathias Stearn
Resolution: Done Votes: 0
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Participants:

 Description   

It would be great to expose the count of fsync() since server startup via the serverStatus() similar to how the number of inserts/updates/delete/querys are exposed. I can/will modify mongostat to read it then. We really want to be able to see fsync's in the output, and it would be cool to see them in all our metrics. I have noticed in testing a 'stall' at points and I am pretty sure it's fsync() based on iostat, but I would like to see it explicitly in mongo.



 Comments   
Comment by Kenny Gorman [ 03/Jun/10 ]

Got it. thx!

Comment by Eliot Horowitz (Inactive) [ 03/Jun/10 ]

It only counts background fsyncs at this point.

Comment by Kenny Gorman [ 03/Jun/10 ]

Oh shoot. I was looking at mongos. I see flushes now.

However, there is another question now.

I an running:

http://pastie.org/990729

I don't see flushes incrementing when I call fsync(). What am I missing? It does appear to increment over time based on perhaps background fsync()'s

Comment by Eliot Horowitz (Inactive) [ 02/Jun/10 ]

@kenny - looks like you're talking to a mongos - which doesn't do any flushing

Comment by Kenny Gorman [ 02/Jun/10 ]

Hmm, what am I missing. I don't see it in 1.5.2.

http://pastie.org/989863

-kg

Comment by Kenny Gorman [ 24/May/10 ]

excellent. thx.

Comment by Mathias Stearn [ 24/May/10 ]

This was added a while ago:

in db.serverStatus():

"backgroundFlushing" :

{ "flushes" : 7, "total_ms" : 501, "average_ms" : 71.57142857142857, "last_ms" : 143, "last_finished" : "Mon May 24 2010 15:23:45 GMT-0400 (EDT)" }

,

The stat you are asking for is in "flushes".

Generated at Thu Feb 08 02:56:08 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.