[ 
https://issues.apache.org/jira/browse/KAFKA-3904?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15350018#comment-15350018
 ] 

Henry Cai commented on KAFKA-3904:
----------------------------------

I have the fix also:

-        FileChannel channel = new RandomAccessFile(lockFile, "rw").getChannel(
+        FileChannel channel = null;
+        synchronized (channels) {
+            channel = channels.get(lockFile);
+            if (channel == null) {
+                channel = new RandomAccessFile(lockFile, "rw").getChannel();
+                channels.put(lockFile, channel);
+                log.info("Creating new channel: {} for file: {}", channel, loc
+            }
+        }
 

> File descriptor leaking (Too many open files) for long running stream process
> -----------------------------------------------------------------------------
>
>                 Key: KAFKA-3904
>                 URL: https://issues.apache.org/jira/browse/KAFKA-3904
>             Project: Kafka
>          Issue Type: Bug
>          Components: streams
>            Reporter: Henry Cai
>            Assignee: Henry Cai
>              Labels: api, newbie
>
> I noticed when my application was running long (> 1 day), I will get 'Too 
> many open files' error.
> I used 'lsof' to list all the file descriptors used by the process, it's over 
> 32K, but most of them belongs to the .lock file, e.g. this same lock file 
> shows 2700 times.
> I looked at the code, I think the problem is in:
>     File lockFile = new File(stateDir, ProcessorStateManager.LOCK_FILE_NAME);
>     FileChannel channel = new RandomAccessFile(lockFile, "rw").getChannel();
> Each time new RandomAccessFile is called, a new fd will be created, we 
> probably should either close or reuse this RandomAccessFile object.
> lsof result:
> java    14799 hcai *740u   REG                9,0        0 2415928585 
> /mnt/stream/join/rocksdb/ads-demo-30/0_16/.lock
> java    14799 hcai *743u   REG                9,0        0 2415928585 
> /mnt/stream/join/rocksdb/ads-demo-30/0_16/.lock
> java    14799 hcai *746u   REG                9,0        0 2415928585 
> /mnt/stream/join/rocksdb/ads-demo-30/0_16/.lock
> java    14799 hcai *755u   REG                9,0        0 2415928585 
> /mnt/stream/join/rocksdb/ads-demo-30/0_16/.lock
> hcai@teststream02001:~$ lsof -p 14799 | grep lock | grep 0_16  | wc
>    2709   24381  319662



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to