Vijay, Thanks for the suggestion. Row Key size is 8 bytes (its a long). Is the issue here incorrect calculation really? The server already had the key cache in memory when i stopped it, and it was using abt 6 gigs of heap total. How is it tht it cannot startup again with the same keycache?
/G On Thu, Jun 28, 2012 at 4:25 PM, Vijay <vijay2...@gmail.com> wrote: > > It has 13.7million keys > How big is your Row Keys? Current calculation (in 1.1) assumes that the > average size of the Entry<RowKey, Long> in the keycache is 16 bytes. > > One thing which you can do to get out this issue is to reduce the Keycache > to a low enough to get the server started or increase the Heap to hold all > the objects. (If you are using the visualVM try to see the object counts). > > Regards, > </VJ> > > > > > On Thu, Jun 28, 2012 at 3:40 PM, Gurpreet Singh > <gurpreet.si...@gmail.com>wrote: > >> Vijay, >> I am running into an issue right now, not sure if its related to this one. >> >> My cassandra 1.1 was running fine for a week, and the key cache size (as >> checked by jconsole) increased to almost 650 mb. It has 13.7million keys. I >> have set key_cache_size_in_mb to 800 mb. I checked the heap size, and it >> was at 6 gigs. All good! >> However, when i try to restart cassandra, it is unable to start now. >> Before i shut it down, it seemed fine at 6 gigs, which means its able to >> handle the memory requirements just fine. However it is not able to start >> up anymore with the same key cache. jconsole says that the heap is full. >> >> Thanks >> /G >> >> >> On Thu, Jun 28, 2012 at 12:22 PM, Vijay <vijay2...@gmail.com> wrote: >> >>> in 1.1 we dont calculate the Key size accurately, hence we have the fix >>> in https://issues.apache.org/jira/browse/CASSANDRA-4315 >>> >>> Regards, >>> </VJ> >>> >>> >>> >>> >>> On Thu, Jun 28, 2012 at 11:25 AM, Gurpreet Singh < >>> gurpreet.si...@gmail.com> wrote: >>> >>>> anyone have an explanation for this? >>>> This kinda screws up memory calculations. >>>> >>>> /G >>>> >>>> On Mon, Jun 25, 2012 at 5:50 PM, Gurpreet Singh < >>>> gurpreet.si...@gmail.com> wrote: >>>> >>>>> Hi, >>>>> I have a question about cassandra 1.1 >>>>> >>>>> Just wanted to confirm if key_cache_size_in_mb is the maximum amount >>>>> of memory that key cache will use in memory? If not, what is it? >>>>> >>>>> My observations: >>>>> With key cache disabled, I started cassandra. I invoked Full GC >>>>> through jconsole a couple of times just to make sure that memory is freed >>>>> up. >>>>> Total heap memory in use is 2.2 gigs. I have almost 550 million keys, >>>>> so this looked reasonable as the bloom filter itself is around 1 gig. >>>>> >>>>> I enabled key cache again by making key_cache_size_in_mb to a value >>>>> 800. This would lead cassandra to load a previously saved key cache file >>>>> of >>>>> size 98 mb on disk. I restarted cassandra again. This time the heap size >>>>> increased to 4.2 gigs. I checked the cache sizing in jconsole. >>>>> >>>>> KeyCacheCapacityInMb: 799 >>>>> KeyCacheSize: 410,316,048 >>>>> >>>>> This says that the key cache size is 410 mb. However the increase in >>>>> the heap is 2 gigs. Doesnt add up!! >>>>> >>>>> Can anyone explain this? >>>>> Thanks >>>>> Gurpreet >>>>> >>>> >>>> >>> >> >
