Re: One big giant cluster or several smaller ones?

2021-11-13 Thread S G
Jirsa wrote: > Oh sorry - a cluster per application makes sense. Sharding within an > application makes sense to avoid very very very large clusters (think: > ~thousand nodes). 1 cluster per app/use case. > > On Fri, Nov 12, 2021 at 1:39 PM S G wrote: > >> Thanks

Re: One big giant cluster or several smaller ones?

2021-11-12 Thread S G
se case / table can ruin > everything (one bad read that generates GC hits all use cases), and > eventually certain mechanisms/subsystems dont scale past certain points > (e.g. schema - large schemas and large clusters are much harder than small > schemas and small clusters) > > > &g

One big giant cluster or several smaller ones?

2021-11-12 Thread S G
Hello, Is there any case where we would prefer one big giant cluster (with multiple large tables) over several smaller clusters? Apart from some management overhead of multiple Cassandra Clients, it seems several smaller clusters are always better than a big one: 1. Avoids SPOF for all tables

How to find traffic profile per client on a Cassandra server?

2021-10-24 Thread S G
Hello, We recently faced an issue recently where the read traffic on a big Cassandra cluster shot up several times (think more than 20 times). However, the client team denies sending any huge load and they have their own traffic graphs to prove the same. Assuming the client team's graphs are

Re: Single node slowing down queries in a large cluster

2021-10-17 Thread S G
will not shoot up in proportion to server's degrading health and hence might be very good to use. Can someone share how big of a time-period is used to calculate the percentile? On Sun, Oct 17, 2021 at 1:59 PM S G wrote: > > "The harder thing to solve is a bad coordinator node slowi

Re: Single node slowing down queries in a large cluster

2021-10-17 Thread S G
te sooner when > that one host gets sick. > > The harder thing to solve is a bad coordinator node slowing down all reads > coordinated by that node. Retry at the client level to work around that > tends to be effective. > > > > On Wed, Oct 13, 2021 at 2:22 PM S G wrote: > >>

Re: Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-13 Thread S G
I see. Thanks Jeff ! On Wed, Oct 13, 2021 at 2:25 PM Jeff Jirsa wrote: > Convention in the yaml is default being visible commented out. > > > On Wed, Oct 13, 2021 at 2:17 PM S G wrote: > >> ok, the link given has the value commented, so I was a bit confused. >>

Re: Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-13 Thread S G
gt; https://github.com/apache/cassandra/blob/trunk/conf/cassandra.yaml#L1000 > > There is no equivalent to `alter system kill session`, because it is > assumed that any query has a short, finite life in the order of seconds. > > > > On Wed, Oct 13, 2021 at 11:10 AM S G wrote: >

Single node slowing down queries in a large cluster

2021-10-13 Thread S G
Hello, We have frequently seen that a single bad node running slow can affect the latencies of the entire cluster (especially for queries where the slow node was acting as a coordinator). Is there any suggestion to avoid this behavior? Like something on the client side to not query that bad

Re: Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-13 Thread S G
Hello, Does anyone know about the default being turned off for this setting? It seems like a good one to be turned on - why have replicas process something for which coordinator has already sent the timeout to client? Thanks On Tue, Oct 12, 2021 at 11:06 AM S G wrote: > Thanks Bowen. &g

Re: Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-12 Thread S G
12, 2021 at 10:49 AM Bowen Song wrote: > That will depend on whether you have cross_node_timeout enabled. However, > I have to point out that set timeout to 15ms is perhaps not a good idea, > the JVM GC can easily cause a lots of timeouts. > On 12/10/2021 18:20, S G wrote:

Re: Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-12 Thread S G
: > It sends an exception to the client, it doesnt sever the connection. > > > On Tue, Oct 12, 2021 at 10:06 AM S G wrote: > >> Do the timeout values only kill the connection with the client or send >> error to the client? >> Or do they also kill the corres

Re: Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-12 Thread S G
out values do this today. > > > https://github.com/apache/cassandra/blob/trunk/conf/cassandra.yaml#L920-L943 > > > On Tue, Oct 12, 2021 at 9:53 AM S G wrote: > >> Hello, >> >> Is there a way to stop long running queries in Cassandra (versions 3.11.x >>

Stop long running queries in Cassandra 3.11.x or Cassandra 4.x

2021-10-12 Thread S G
Hello, Is there a way to stop long running queries in Cassandra (versions 3.11.x or 4.x) ? The use-case is to have some kind of a circuit breaker based on query-time that has exceeded the client's SLAs. Example: If server response is useless to the client after 10 ms, then we could have a

Re: Does Open-Source Cassandra 4 support mutual-TLS ?

2021-09-21 Thread S G
> > > On Sep 21, 2021, at 11:59 AM, S G wrote: > > > > Hello, > > > > Does anyone know if opensource Cassandra support mutual-TLS ? > > The documentation doesn't conclusively deny or accept the support for > the same. > > > > Thanks ! > >

Does Open-Source Cassandra 4 support mutual-TLS ?

2021-09-21 Thread S G
Hello, Does anyone know if opensource Cassandra support mutual-TLS ? The documentation doesn't conclusively deny or accept the support for the same. Thanks !

How many coordinator nodes in the cluster at a given time?

2021-09-13 Thread S G
Hello, As mentioned in https://cassandra.apache.org/_/cassandra-basics.html, can someone clarify how many coordinator nodes are there in the cluster at any given time? 1. Is there a dedicated *single* coordinator node in the whole cluster that changes from time to time? 2. Or any node

DataStax: What codec to use for converting bigint to Long?

2017-03-30 Thread S G
Hi, I have a bigint field in my Cassandra that I want to convert to a long value. However, I am not sure how to specify the same in my DataStax-mapper-entity-class. Here is the code: @PartitionKey(1) @Column(name="phone", codec=TypeCodec.) private Double phoneNumber; Can someone please tell

Re: Weird error: InvalidQueryException: unconfigured table table2

2017-03-26 Thread S G
t; Thanks >> Anuj >> >> Sent from Yahoo Mail on Android >> <https://overview.mail.yahoo.com/mobile/?.src=Android> >> >> On Sat, Mar 25, 2017 at 3:19 AM, S G >> <sg.online.em...@gmail.com> wrote: >> Hi, >> >> I have a keyspace with two tables. >

Using datastax driver, how can I read a non-primitive column as a JSON string?

2017-03-23 Thread S G
Hi, I have several non-primitive columns in my cassandra tables. Some of them are user-defined-types UDTs. While querying them through datastax driver, I want to convert such UDTs into JSON values. More specifically, I want to get JSON string for the value object below: Row row =

Re: How can I scale my read rate?

2017-03-18 Thread S G
Forgot to mention that this vmstat picture is for the client-cluster reading from Cassandra. On Sat, Mar 18, 2017 at 6:47 PM, S G <sg.online.em...@gmail.com> wrote: > ok, I gave the executeAsync() a try. > Good part is that it was really easy to write the code for that. > Bad part

Re: How can I scale my read rate?

2017-03-18 Thread S G
andra cluster with 16 VMs, 8-core each too. ​ ​ Thanks SG On Sat, Mar 18, 2017 at 5:38 PM, S G <sg.online.em...@gmail.com> wrote: > Thanks. It seems that you guys have found executeAsync to yield good > results. > I want to share my understanding how this could benefit performanc

Re: How can I scale my read rate?

2017-03-18 Thread S G
ipelining. Use executeAsync > - this will increase your throughput for sure. > > > > http://www.datastax.com/dev/blog/java-driver-async-queries > > > > > > On Sat, Mar 18, 2017 at 08:00 S G <sg.online.em...@gmail.com> wrote: > > I have enabled JMX but not sure wh