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Posted to mapreduce-issues@hadoop.apache.org by "Sergey Tryuber (Created) (JIRA)" <ji...@apache.org> on 2012/02/14 10:03:59 UTC
[jira] [Created] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
------------------------------------------------------------------------------------
Key: MAPREDUCE-3859
URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
Project: Hadoop Map/Reduce
Issue Type: Bug
Components: contrib/capacity-sched
Environment: CDH3u1
Reporter: Sergey Tryuber
Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13208204#comment-13208204 ]
Arun C Murthy commented on MAPREDUCE-3859:
------------------------------------------
Sergey, I'm pretty sure the reason you are hitting this is that you have a single user in your queue.
By default, a single user can't exceed the queue's capacity (10 in this case). You can use 'user-limit-factor' to bump that up: http://hadoop.apache.org/common/docs/r1.0.0/capacity_scheduler.html#Configuration
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Issue Comment Edited] (MAPREDUCE-3859) CapacityScheduler
incorrectly utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Issue Comment Edited) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209461#comment-13209461 ]
Arun C Murthy edited comment on MAPREDUCE-3859 at 2/16/12 3:54 PM:
-------------------------------------------------------------------
Thanks, I'll run the test.
Also, maybe the fix would be better expressed as:
{code}
int currentCapacity = max(queueSlotsOccupied, queueCapacity) + numSlotsRequested;
{code}
was (Author: acmurthy):
Thanks, I'll run the test.
Also, maybe the fix would be better expressed as:
{code}
int currentCapacity = min(queueSlotsOccupied, queueCapacity) + numSlotsRequested;
{code}
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
> Attachments: test-to-fail.patch.txt
>
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Updated] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Harsh J (Updated) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Harsh J updated MAPREDUCE-3859:
-------------------------------
Target Version/s: 1.1.0
Affects Version/s: 1.0.0
This affects 1.x as well, comparing the difference in commits to CS between CDH3's CS and Apache 1.x.
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209086#comment-13209086 ]
Arun C Murthy commented on MAPREDUCE-3859:
------------------------------------------
Sergey - can you please try this again by bumping up user-limit-factor to 2 or 3?
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209461#comment-13209461 ]
Arun C Murthy commented on MAPREDUCE-3859:
------------------------------------------
Thanks, I'll run the test.
Also, maybe the fix would be better expressed as:
{code}
int currentCapacity = min(queueSlotsOccupied, queueCapacity) + numSlotsRequested;
{code}
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
> Attachments: test-to-fail.patch.txt
>
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Sergey Tryuber (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209145#comment-13209145 ]
Sergey Tryuber commented on MAPREDUCE-3859:
-------------------------------------------
We've tried to play with user-limit-factor in any variants (2,3, 10, 100 and even more). Well, Arun, I just write a test for CapacityScheduler (this test should fail). Before preparing any patches, I'll put the code here and you'll take a look on it. Ok?
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209177#comment-13209177 ]
Arun C Murthy commented on MAPREDUCE-3859:
------------------------------------------
I'm not against fixing the CS, I just want to ensure we do the 'right' fix.
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Updated] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Sergey Tryuber (Updated) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Sergey Tryuber updated MAPREDUCE-3859:
--------------------------------------
Attachment: test-to-fail.patch.txt
Patch with test which fails for high memory jobs
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
> Attachments: test-to-fail.patch.txt
>
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Sergey Tryuber (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209243#comment-13209243 ]
Sergey Tryuber commented on MAPREDUCE-3859:
-------------------------------------------
Arun, Harsh, I've submitted patch (test-to-fail.patch.txt) with test (it should be applied against "branch-1.0" branch).
Test creates 20 map slots cluster (5 nodes with 4 slots) and queue with capacity 10 slots, max capacity 16 slots, user limit factor 2. The cluster is idle. When we submit high memory job (5 mappers with 4 slots per mapper), it should consume 16 slots (4 mappers should be run), but it doesn't because of the bug.
Test with fix (fix is not in the patch) works well.
Feel free to give any remarks (about code style, for example), because that's my first hadoop coding. Arun, agree with you, that each bug report should be "double-checked".
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
> Attachments: test-to-fail.patch.txt
>
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Sergey Tryuber (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13207611#comment-13207611 ]
Sergey Tryuber commented on MAPREDUCE-3859:
-------------------------------------------
Sorry, I don't know what exactly version of Hadoop is used in cdh3u1 distribution. There we have following lines in *CapacitySchedulerQueue.java* in *assignSlotsToJob* method:
{code}
int queueSlotsOccupied = getNumSlotsOccupied(taskType);
int currentCapacity;
if (queueSlotsOccupied < queueCapacity) {
currentCapacity = queueCapacity;
}
else {
currentCapacity = queueSlotsOccupied + numSlotsRequested;
}
{code}
Imagine we have a job with 1 slot per task, if we have queue with 10 configured capacity and 9 occupied slots (imagine, we have large maximum capacity and a lot of free slots on cluster), then _currentCapacity=10_ and task will be scheduled properly. Later, when will have 10 occupied slots, _currentCapacity=11_ and all will be fine too. And so on...
Now imagine, we have a job with 3 slots per task, if we have queue with 10 configured capacity and 9 occupied slots, then _currentCapacity=10_, but that's not enough for scheduling this new task!!! So, this job will never use more then 9 slots!
I've fixed this problem by changing:
{code}
if (queueSlotsOccupied < queueCapacity) {
{code}
on
{code}
if (queueSlotsOccupied + numSlotsRequested <= queueCapacity) {
{code}
I've rebuilt cdh3u1 from sources, deployed jar on the cluster and CapacityScheduler works well now for me.
Also I've checkouted current Hadoop's trunk. Unfortunately, sources of CapacityScheduler dramatically changed. But I've found the similar lines in *LeafQueue.java* in *computeUserLimit* method:
{code}
final int currentCapacity =
(consumed < queueCapacity) ?
queueCapacity : (consumed + required.getMemory());
{code}
So, it seems to me, this bug also affects the latest CapacityScheduler
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209464#comment-13209464 ]
Arun C Murthy commented on MAPREDUCE-3859:
------------------------------------------
Hmm... maybe not.
Let me think more about it's implications on user-limit etc.
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
> Attachments: test-to-fail.patch.txt
>
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Arun C Murthy (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13209154#comment-13209154 ]
Arun C Murthy commented on MAPREDUCE-3859:
------------------------------------------
That would be great, thanks.
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Harsh J (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13207680#comment-13207680 ]
Harsh J commented on MAPREDUCE-3859:
------------------------------------
Sergey,
Thanks for taking a dig at the code and coming up with a fix! Would you be interested in posting a patch fix for this as well? We'd require a test case that fails without the fix as well.
Let us know if thats possible, thanks again!
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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[jira] [Commented] (MAPREDUCE-3859) CapacityScheduler incorrectly
utilizes extra-resources of queue for high-memory jobs
Posted by "Sergey Tryuber (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/MAPREDUCE-3859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13208337#comment-13208337 ]
Sergey Tryuber commented on MAPREDUCE-3859:
-------------------------------------------
Arun, no, that's not 'user-limit-factor' issue(( This option perfectly works in case if job consumes only 1 slot per task and we've been using this option for a while. This bug affects only cases if job consumes more than one slot per task.
Harsh, what version should I try to patch? Is it branch-1.0? Or trunk too?
> CapacityScheduler incorrectly utilizes extra-resources of queue for high-memory jobs
> ------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3859
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3859
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/capacity-sched
> Affects Versions: 1.0.0
> Environment: CDH3u1
> Reporter: Sergey Tryuber
>
> Imagine, we have a queue A with capacity 10 slots and 20 as extra-capacity, jobs which use 3 map slots will never consume more than 9 slots, regardless how many free slots on a cluster.
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