Local cache + FileCacheStore -> many 0-byte Files left behind

[tfromm]

ISPN: 5.1.0 CR1

OS: Linux

My scenario: I create lots of entries and remove them from cache. The key values are very different strings and so the number of left behind 0-byte files increases very fast.

Example 1:

	byte[] data = "ABCDEFG".getBytes();
	e05.put("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", data);
	e05.remove("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
	e05.put("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1", data);
	e05.remove("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1");

Two files left behind:

-rw-r--r-- 1 tf tape	0 21. Dez 11:46 1358968832
-rw-r--r-- 1 tf tape	0 21. Dez 11:46 459479040

Example 2:

	byte[] data = "ABCDEFG".getBytes();
	e05.put("A", data);
	e05.remove("A");
	e05.put("B", data);
	e05.remove("B");

Only one file is left behind:

-rw-r--r-- 1 tf tape

0 21. Dez 11:50 0

Any ideas how to solve that behaviour?

[manik]

This is expected behaviour.  This was brought up and discussed on infinispan-dev, see this thread for details.  Basically, in summary, it is too expensive to clean up these files - as this involves locks - only to find that they may be recreated again by a concurrent thread.  So the task of removing 0-byte files is left to the expiration reaper thread when purgeExpired() is called on the CacheStore.

So if you have a reaper thread enabled, you should see these being removed from time to time.

[tfromm]

I'll perform closer investigation on this these days. Thanks for the fast response

https://issues.jboss.org/browse/ISPN-1645