> If node is low on memory 0.95+ heap used it can do: > > 1. stop repair > 2. stop largest compaction > 3. reduce number of compaction slots > 4. switch compaction to single threaded > > flushing largest memtable/ cache reduce is not enough
Note that the "emergency" flushing is just a stop-gap. You should run with appropriately sized heaps under normal conditions; the emergency flushing stuff is intended to mitigate the effects of having a too small heap size; it is not expected to avoid completely the detrimental effects. Also note that things like compaction does not normally contribute significantly to the live size on your heap, but it typically does contribute to allocation rate which can cause promotion failures or concurrent mode failures if your heap size is too small and/or concurrent mark/sweep settings not aggressive enough. Aborting compaction wouldn't really help anything other than short-term avoiding a fallback to full GC. I suggest you describe exactly what the problem is you have and why you think stopping compaction/repair is the appropriate solution. -- / Peter Schuller (@scode, http://worldmodscode.wordpress.com)
