• Bug
  • Status: Closed
  • 1 Critical
  • Resolution: Won't Fix
  • ehcache-core
  • cdennis
  • Reporter: cdennis
  • October 11, 2010
  • 2
  • Watchers: 1
  • July 27, 2012
  • July 23, 2011

Description

See discussion here: http://forums.terracotta.org/forums/posts/list/4319.page

In short when there are many more disk elements than in-memory elements the in-memory eviction sample selection can take a logn time due to the number of misses when trying to find in-memory mappings in the CompoundStore.

One possible solution to this would be to keep an aproximation version of the in-memory key set in a secondary data structure.

Comments

Fiona OShea 2010-10-12

Per Mike: Do not hold Magnum release for this issue.

gluck 2011-01-05

The MemoryStore evictor stops working effectively when you have a DiskStore turned on. The likely effect is an OutOfMemory error. This was caused by the unified stores and was introduced in 2.1.

Of all the bugs I know about this one concerns me the most. If possible it would be good to get this fixed as this bug could do damage to us out there.

Chris Dennis 2011-01-05

Not sure how this could cause an OutOfMemoryError? The slow eviction process happens inline with the puts, app threads take longer to perform the puts due to this but nothing should cause an increase in memory usage.

Chris Dennis 2011-01-07

As discussed in email conversation, I am upping the priority of this to P1 and moving it out to Ulloa.

david snowsill 2011-07-23

Any thoughts on when this will be fixed?

Chris Dennis 2011-07-23

Resolving this as “Won’t Fix” - although it could equally well be “Not a Bug”. For the upcoming Ehcache 2.5 release this is “Not a Bug” as the way the disk and memory elements are stored has been changed due to the arrival of the cache manager level resource management code. It is unlikely however that this will be fixed in any earlier lines.