Gert,
What version of Hadoop are you using?

One of the people at my work who is using 0.17.1 is reporting a similar
problem - namenode's heapspace filling up too fast.

This is the status of his cluster (17 node cluster with version 0.17.1)
*- 174541 files and directories, 121000 blocks = 295541 total. Heap Size is
898.38 MB / 1.74 GB (50%) **
*
Here is the status of one of my clusters. (70 node cluster with version
0.16.3)
- *265241 files and directories, 1155060 blocks = 1420301 total. Heap Size
is 797.94 MB / 1.39 GB (56%)*
**
Notice that the second cluster has about 9 times more blocks than the first
one (and more files and dir's, too) but heap usage is in similar figures
(actually smaller...)

Has anyone also noticed any problems/inefficiencies in namenode's memory
utilization in 0.17.x version?




On Mon, Jul 28, 2008 at 2:13 AM, Gert Pfeifer
<[EMAIL PROTECTED]>wrote:

> There I have:
>   export HADOOP_HEAPSIZE=8000
> ,which should be enough (actually in this case I don't know).
>
> Running the fsck on the directory it turned out that there are 1785959
> files in this dir... I have no clue how I can get  the data out of there.
> Can I somehow calculate, how much heap a namenode would need to do an ls on
> this dir?
>
> Gert
>
>
> Taeho Kang schrieb:
>
> Check how much memory is allocated for the JVM running namenode.
>>
>> In a file HADOOP_INSTALL/conf/hadoop-env.sh
>> you should change a line that starts with "export HADOOP_HEAPSIZE=1000"
>>
>> It's set to 1GB by default.
>>
>>
>> On Fri, Jul 25, 2008 at 2:51 AM, Gert Pfeifer <
>> [EMAIL PROTECTED]>
>> wrote:
>>
>> Update on this one...
>>>
>>> I put some more memory in the machine running the name node. Now fsck is
>>> running. Unfortunately ls fails with a time-out.
>>>
>>> I identified one directory that causes the trouble. I can run fsck on it
>>> but not ls.
>>>
>>> What could be the problem?
>>>
>>> Gert
>>>
>>> Gert Pfeifer schrieb:
>>>
>>> Hi,
>>>
>>>> I am running a Hadoop DFS on a cluster of 5 data nodes with a name node
>>>> and one secondary name node.
>>>>
>>>> I have 1788874 files and directories, 1465394 blocks = 3254268 total.
>>>> Heap Size max is 3.47 GB.
>>>>
>>>> My problem is that I produce many small files. Therefore I have a cron
>>>> job which just runs daily across the new files and copies them into
>>>> bigger files and deletes the small files.
>>>>
>>>> Apart from this program, even a fsck kills the cluster.
>>>>
>>>> The problem is that, as soon as I start this program, the heap space of
>>>> the name node reaches 100 %.
>>>>
>>>> What could be the problem? There are not many small files right now and
>>>> still it doesn't work. I guess we have this problem since the upgrade to
>>>> 0.17.
>>>>
>>>> Here is some additional data about the DFS:
>>>> Capacity         :       2 TB
>>>> DFS Remaining   :       1.19 TB
>>>> DFS Used        :       719.35 GB
>>>> DFS Used%       :       35.16 %
>>>>
>>>> Thanks for hints,
>>>> Gert
>>>>
>>>>
>>>
>>
>

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