Re: Cassandra Counters

Hi Tarun, That documentation page is a bit ambiguous. My understanding of it is that: * Cassandra guarantees that counters are updated consistently across the cluster by doing background reads, that don't affect write latency. * If you use a consistency level stricter than ONE, the same read is d

Re: Cassandra counters

Any pointers on this?. In 2.1, when updating the counter with UNLOGGED batch using timestamp isn't safe as other column update with consistency level (with timestamp counter update can be idempotent? ). Thanks Ajay On 09-Jul-2015 11:47 am, "Ajay" wrote: > > Hi, > > What is the accuracy improvem

Re: Cassandra counters replication uses more traffic than client increments?

Since you're asking about counters, I'll note too that the internal representation of counters is pretty fat. In you RF=2 case, each counter is probably about 64 bytes internally, while on the client side you send only a 8 bytes value for each increment. So I don't think there is anything unexpecte

Re: Cassandra counters replication uses more traffic than client increments?

Can you measure the incoming client traffic on the nodes in DC 1 on port 9160 ? That would be more of an Apples to Apples comparison. >> I've taken a look at some of the captured packets and it looks like >> there's much more service information in DC-to-DC traffic compared to >> client-to-serve

Re: Cassandra counters replication uses more traffic than client increments?

So with the holidays hopefully being over, I thought I'd ask again :) Could someone please help with answers to the two questions: - Is it reasonable to expect that cross-datacenter node-to-node replication traffic is greater than actual client-to-server traffic that generates this activity? Speci

Re: Cassandra Counters

> In a relatively untroubled cluster, even timed out writes go through, > provided no messages are dropped. This all depends of your definition of "untroubled" cluster, but to be clear, in a cluster where a node dies (which for Cassandra is not considered abnormal and will happen to everyone no ma

Re: Cassandra Counters

@Sylvain and @Rohit: Thanks for your answers. On Tue, Sep 25, 2012 at 2:27 PM, Sylvain Lebresne wrote: > So general question, should I rely on Counters if I want 100% accuracy? >> > > No. > > Even not considering potential bugs, counters being not idempotent, if > you get a TimeoutException dur

Re: Cassandra Counters

@Sylvain In a relatively untroubled cluster, even timed out writes go through, provided no messages are dropped. Which you can monitor on cassandra nodes. We have 100% consistency on our production servers as we don't see messages being dropped on our servers. Though as you mention, there would be

Re: Cassandra Counters

> > So general question, should I rely on Counters if I want 100% accuracy? > No. Even not considering potential bugs, counters being not idempotent, if you get a TimeoutException during a write (which can happen even in relatively normal conditions), you won't know if the increment went in or n

Re: Cassandra Counters

c. >>> >>> Given this, what are the performance tradeoffs of using counters vs a >>> standard column family for counting. Because as I see if the counter number >>> in a counter column family becomes wrong, it will not be 'eventually >>&g

Re: Cassandra Counters

vs a >> standard column family for counting. Because as I see if the counter number >> in a counter column family becomes wrong, it will not be 'eventually >> consistent' - you will need intervention to correct it. So the key aspect >> is how much faster would be a c

Re: Cassandra Counters

So the key aspect > is how much faster would be a counter column family, and at what numbers do > we start seing a difference. > > > > > > -- > Date: Tue, 25 Sep 2012 07:57:08 +0200 > Subject: Re: Cassandra Counters > From: oleksandr.pet.

RE: Cassandra Counters

ventually consistent' - you will need intervention to correct it. So the key aspect is how much faster would be a counter column family, and at what numbers do we start seing a difference. Date: Tue, 25 Sep 2012 07:57:08 +0200 Subject: Re: Cassandra Counters From: oleksandr.

Re: Cassandra Counters

nts and decrements to the count. > Any comparisons in performance to using counter column families? > > Regards, > Roshni > > > ---------- > Date: Mon, 24 Sep 2012 11:02:51 -0700 > Subject: RE: Cassandra Counters > From: milindpar...@gmail.com > To: use

RE: Cassandra Counters

Thanks Milind, Has anyone implemented counting in a standard col family in cassandra, when you can have increments and decrements to the count. Any comparisons in performance to using counter column families? Regards,Roshni Date: Mon, 24 Sep 2012 11:02:51 -0700 Subject: RE: Cassandra Counters

RE: Cassandra Counters

IMO You would use Cassandra Counters (or other variation of distributed counting) in case of having determined that a centralized version of counting is not going to work. You'd determine the non_feasibility of centralized counting by figuring the speed at which you need to sustain writes and rea

RE: Cassandra Counters

Hi folks, I looked at my mail below, and Im rambling a bit, so Ill try to re-state my queries pointwise. a) what are the performance tradeoffs on reads & writes between creating a standard column family and manually doing the counts by a lookup on a key, versus using counters. b) whats the

Re: Cassandra Counters and TTL

On Mon, Nov 7, 2011 at 10:12 AM, Vlad Paiu wrote: > Hello, > > Thanks for your answer. See my reply in-line. > > On 11/04/2011 01:46 PM, Amit Chavan wrote: > > Answers inline. > > On Fri, Nov 4, 2011 at 4:59 PM, Vlad Paiu wrote: >> >> Hello, >> >> I'm a new user of Cassandra and I think it's grea

Re: Cassandra Counters and TTL

Hello, Thanks for your answer. See my reply in-line. On 11/04/2011 01:46 PM, Amit Chavan wrote: Answers inline. On Fri, Nov 4, 2011 at 4:59 PM, Vlad Paiu > wrote: Hello, I'm a new user of Cassandra and I think it's great. Still, while developing my

Re: Cassandra Counters and TTL

Answers inline. On Fri, Nov 4, 2011 at 4:59 PM, Vlad Paiu wrote: > Hello, > > I'm a new user of Cassandra and I think it's great. > Still, while developing my APP using Cassandra, I got stuck with some > things and I'm not really sure that Cassandra can handle them at the moment. > > So, first o

Re: Cassandra Counters and Replication Factor

On Wed, Oct 12, 2011 at 9:37 AM, Amit Chavan wrote: > Hi, > Looking at this talk > (http://www.datastax.com/wp-content/uploads/2011/07/cassandra_sf_counters.pdf) > by Sylvain Lesbresne at DataStax, I had a few questions related to my > understanding Cassandra architecture. > Assuming that we have