You, and only you, are responsible for knowing your data and data model. If columns per row or rows per partition can be large, then an 8GB system is probably too small. But the real issue is that you need to keep your partition size from getting too large.
Generally, an 8GB system is okay, but only for reasonably-sized partitions, like under 10MB. -- Jack Krupansky On Fri, Jul 10, 2015 at 8:05 AM, Kunal Gangakhedkar <kgangakhed...@gmail.com > wrote: > I'm new to cassandra > How do I find those out? - mainly, the partition params that you asked > for. Others, I think I can figure out. > > We don't have any large objects/blobs in the column values - it's all > textual, date-time, numeric and uuid data. > > We use cassandra to primarily store segmentation data - with segment type > as partition key. That is again divided into two separate column families; > but they have similar structure. > > Columns per row can be fairly large - each segment type as the row key and > associated user ids and timestamp as column value. > > Thanks, > Kunal > > On 10 July 2015 at 16:36, Jack Krupansky <jack.krupan...@gmail.com> wrote: > >> What does your data and data model look like - partition size, rows per >> partition, number of columns per row, any large values/blobs in column >> values? >> >> You could run fine on an 8GB system, but only if your rows and partitions >> are reasonably small. Any large partitions could blow you away. >> >> -- Jack Krupansky >> >> On Fri, Jul 10, 2015 at 4:22 AM, Kunal Gangakhedkar < >> kgangakhed...@gmail.com> wrote: >> >>> Attaching the stack dump captured from the last OOM. >>> >>> Kunal >>> >>> On 10 July 2015 at 13:32, Kunal Gangakhedkar <kgangakhed...@gmail.com> >>> wrote: >>> >>>> Forgot to mention: the data size is not that big - it's barely 10GB in >>>> all. >>>> >>>> Kunal >>>> >>>> On 10 July 2015 at 13:29, Kunal Gangakhedkar <kgangakhed...@gmail.com> >>>> wrote: >>>> >>>>> Hi, >>>>> >>>>> I have a 2 node setup on Azure (east us region) running Ubuntu server >>>>> 14.04LTS. >>>>> Both nodes have 8GB RAM. >>>>> >>>>> One of the nodes (seed node) died with OOM - so, I am trying to add a >>>>> replacement node with same configuration. >>>>> >>>>> The problem is this new node also keeps dying with OOM - I've >>>>> restarted the cassandra service like 8-10 times hoping that it would >>>>> finish >>>>> the replication. But it didn't help. >>>>> >>>>> The one node that is still up is happily chugging along. >>>>> All nodes have similar configuration - with libjna installed. >>>>> >>>>> Cassandra is installed from datastax's debian repo - pkg: dsc21 >>>>> version 2.1.7. >>>>> I started off with the default configuration - i.e. the default >>>>> cassandra-env.sh - which calculates the heap size automatically (1/4 * RAM >>>>> = 2GB) >>>>> >>>>> But, that didn't help. So, I then tried to increase the heap to 4GB >>>>> manually and restarted. It still keeps crashing. >>>>> >>>>> Any clue as to why it's happening? >>>>> >>>>> Thanks, >>>>> Kunal >>>>> >>>> >>>> >>> >> >
