[SERVER-1134] Increments due to running admin commands Created: 18/May/10 Updated: 12/Jul/16 Resolved: 26/May/10 |
|
| Status: | Closed |
| Project: | Core Server |
| Component/s: | Querying |
| Affects Version/s: | 1.4.2 |
| Fix Version/s: | None |
| Type: | Question | Priority: | Major - P3 |
| Reporter: | Justin Smestad | Assignee: | Eliot Horowitz (Inactive) |
| Resolution: | Done | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Participants: |
| Description |
|
When running db._adminCommand('top') it seems that the values that get sent back are effected by the command. Meaning, I could have 10 queries on a particular collection before running the top command, however after running the top command it jumps up a large amount (have not tested for the exact amount) to something like 120 queries. I spoke with Kyle regarding this and he asked me to open an issue since it may be a bug. We are trying to figure out what and how many times a collection is 'touched' when top is run on the server. |
| Comments |
| Comment by Eliot Horowitz (Inactive) [ 26/May/10 ] |
|
$cmd is all db commands, including top itself. you may want to remove that from your counts |
| Comment by Paul Sadauskas [ 20/May/10 ] |
|
I'm trying to get some more information about this. I'm pretty sure its just a misunderstanding on our end, but I'm having trouble finding docs on what the top command returns. Here's what I've collected: > use mongo_stats ).totals["mongo_stats.raw"]["queries"] { "time" : 18873, "count" : 4 }> db.runCommand( {top: true}).totals["mongo_stats.log"]["queries"] { "time" : 0, "count" : 0 }> db.runCommand( {top: true}).totals["mongo_stats.system.users"]["queries"] { "time" : 1638, "count" : 20 }> db.runCommand( {top: true}).totals["mongo_stats.$cmd"]["queries"] { "time" : 49880, "count" : 43 }> db.runCommand( {top: true}).totals["mongo_stats"]["queries"] { "time" : 9790, "count" : 21 }( http://gist.github.com/407198 if the formatting blows up) What is the $cmd "collection", and what is the last one, with no collection? What commands increment the counters for those stats? The original issue is incorrectly defined, thats not the behavior we're seeing. I've written a script that runs as a cronjob, which takes every entry in runCommand( {top: true})["totals"] and inserts it into a separate db. The cron job runs every 2 minutes, and we have 150 entries in the result of top. However, over the last 3 days, it has done nearly 2 _B_illion requests on that database. I would expect something closer to ( 30 runs/hr * 24h * 3d * 150 results = 300,000 inserts) Here's the client debug log file of a single run: https://gist.github.com/db1e5cfd85ec6efd4d07 . In this screenshot, you can see the results from top: http://skitch.com/theamazingrando/drmac/hosted-mongodb-from-mongo-machine I guess my biggest question is: What exactly does top report? |
| Comment by Eliot Horowitz (Inactive) [ 19/May/10 ] |
|
can you provide an example? |