Size and Capacity are in bytes. The RAM is consumed right after Cassandra
start (3GB heap) - the reason for this could be 400.000.000 rows on single
node, serialized bloom filters take 1,2 GB HDD space.
On Mon, Dec 3, 2012 at 10:14 AM, Maciej Miklas mac.mik...@gmail.com wrote:
Hi,
I have
Hi *,
I would like to use Cassandra to store session related informations. I do
not have real HTTP session - it's different protocol, but the same concept.
Memcached would be fine, but I would like to additionally persist data.
Cassandra setup:
- non replicated Key Space
- single Column
- RF is 1. We have few KeySpaces, only this one is not replicated - this
data is not that very important. In case of error customer will have to
execute process again. But again, I would like to persist it.
- Serializing data is not an option, because I would like to have
possibility to access
durable_writes sounds great - thank you! I really do not need commit log
here.
Another question: it is possible to configure live time of Tombstones?
Regards,
Maciej
Hi all,
I've tested row cache, and find out, that it requires large amount of Heap -
I would like to verify this theory.
This is my test key space:
{
TestCF: {
row_key_1: {
{ clientKey: MyTestCluientKey },
{ tokenSecret: kd94hf93k423kf44 },
{
this is how I tested it:
1) load cache with 1.500.000 entries
2) execute fill gc
3) mesure heap size (using visual vm)
4) execute flush row cahce over cli
5) execute full gc
6) and again mesure hap usage
The difference between 6) and 3) is the heap size used by cache
On Fri, Oct 28, 2011 at
Hi all,
is there any documentation about proper JNA configuration?
I do not understand few things:
1) Does JNA use JVM heap settings?
2) Do I need to decrease max heap size while using JNA?
3) How do I limit RAM allocated by JNA?
4) Where can I see / monitor row cache size?
5) I've
. If you have
received this message in error, please contact the sender immediately and
irrevocably delete this message and any copies.-Original Message-
From: Maciej Miklas [mailto:mac.mik...@googlemail.com]
Sent: Tuesday, November 01, 2011 11:15
To: user@cassandra.apache.org
Subject
On Wed, Nov 2, 2011 at 1:53 PM, Maciej Miklas mac.mik...@googlemail.comwrote:
I've just found, that JNA will be not used from 1.1 release -
https://issues.apache.org/jira/browse/CASSANDRA-3271
I would be also nice to know what was the reason for this decision.
Regards,
Maciej
On Wed, Nov 2
on https://issues.apache.org/jira/browse/CASSANDRA-3143
to make cache sizing easier.
On Thu, Nov 3, 2011 at 3:16 AM, Maciej Miklas mac.mik...@googlemail.com
wrote:
According to source code, JNA is being used to call malloc and free. In
this
case each cached row will be serialized into RAM
I would like to know it also - actually is should be similar, plus there
are no dependencies to sun.misc packages.
Regards,
Maciej
On Thu, Nov 10, 2011 at 1:46 PM, Benoit Perroud ben...@noisette.ch wrote:
Thanks for the answer.
I saw the move to sun.misc.
In what sense allocateDirect is
Hallo all,
I need your help to design structure for simple login service. It contains
about 100.000.000 customers and each one can have about 10 different logins
- this results 1.000.000.000 different logins.
Each customer contains following data:
- one to many login names as string, max 20
: e72c504dc16c8fcd2fe8c74bb492affa
alias1: alfred.tes...@xyz.de
alias2: alf...@aad.de
alias3: a...@dd.de
}
...and you can use secondary indexes to query on anything.
Maxim
On 11/17/2011 4:08 PM, Maciej Miklas wrote:
Hallo all,
I need your help to design
I will follow exactly this solution - thanks :)
On Fri, Nov 18, 2011 at 9:53 PM, David Jeske dav...@gmail.com wrote:
On Thu, Nov 17, 2011 at 1:08 PM, Maciej Miklas
mac.mik...@googlemail.comwrote:
A) Skinny rows
- row key contains login name - this is the main search criteria
- login
Hallo,
assuming Ordered Partitioner I would like to have possibility to find
records by row key range and columns by slice - for example:
Give me all rows between 2001 and 2003 and all columns between A and C.
For such data:
{
2001: {A:v1, Z:v2},
2002: {R:v2, Z:v3},
2003: {C:v4, Z:v5},
I've asked this question already on stackoverflow but without answer - I
wll try again:
My use case expects heavy read load - there are two possible model design
strategies:
1.
Tiny rows with row cache: In this case row is small enough to fit into
RAM and all columns are being cached.
Have you tried to change:
me.prettyprint.cassandra.service.CassandraHostConfigurator#retryDownedHostsDelayInSeconds
?
Hector will ping down hosts every xx seconds and recover connection.
Regards,
Maciej
On Mon, Mar 5, 2012 at 8:13 PM, Daning Wang dan...@netseer.com wrote:
I just got this
Hi *,
I would like to know your opinion about using Cassandra to implement a
RBAC-like authentication authorization model. We have simplified the
central relationship of the general model (
http://en.wikipedia.org/wiki/Role-based_access_control) to:
user ---n:m--- role ---n:m--- resource
multiget would require Order Preserving Partitioner, and this can lead to
unbalanced ring and hot spots.
Maybe you can use secondary index on itemtype - is must have small
cardinality:
http://pkghosh.wordpress.com/2011/03/02/cassandra-secondary-index-patterns/
On Tue, Mar 27, 2012 at 10:10 AM,
yes - but anyway in your example you need key range quey and that
requires OOP, right?
On Tue, Mar 27, 2012 at 5:13 PM, Guy Incognito dnd1...@gmail.com wrote:
multiget does not require OPP.
On 27/03/2012 09:51, Maciej Miklas wrote:
multiget would require Order Preserving Partitioner
need to worry about the case
where you (transiently) have more than 10 'latest' items for a single
itemType.
On 28/03/2012 09:49, Maciej Miklas wrote:
yes - but anyway in your example you need key range quey and that
requires OOP, right?
On Tue, Mar 27, 2012 at 5:13 PM, Guy Incognito dnd1
Hi,
I've seen this blog entry:
http://www.datastax.com/dev/blog/schema-in-cassandra-1-1 and I am trying to
understand, how could Cassandra support PRIMARY KEY.
Cassandra has silent conflict resolution, where each insert overwrites next
one, and there are only inserts and deletes - no updates.
CQL will have UPDATE future, I am trying to understand how this could work.
Every write is an append to SSTable, UPDATE would need to change data, but
only if it exists, and this is problematic, since we have distributed
system.
Is UPDATE special kind of insert, which changes given data only if
Hi all,
older Cassandra versions had to read columns from each SSTable with
positive bloom filter in order to find recent value.
This was optimized with: Improve read performance in update-intensive
workload https://issues.apache.org/jira/browse/CASSANDRA-2498
Now each SSTable has metadata -
Hi all,
bloom filter for row keys is always in RAM. What about SSTable index, and
Metadata?
Is it cached by Cassandra, or it relays on memory mapped files?
Thanks,
Maciej
@aaronmorton
http://www.thelastpickle.com
On 16/08/2012, at 7:34 PM, Maciej Miklas mac.mik...@gmail.com wrote:
Hi all,
bloom filter for row keys is always in RAM. What about SSTable index, and
Metadata?
Is it cached by Cassandra, or it relays on memory mapped files?
Thanks,
Maciej
UnavailableException is bit tricky. It means, that not all replicas
required by CL received update. Actually you do not know, whenever update
was stored or not, and actually what went wrong.
This is the case, why writing with CL.ALL might get problematic. It is
enough, that only one replica is
I'am using Java + Tomcat + Spring + Hector on Lunux - I works as always
just great.
It is also not bad idea to mix databases - Cassandra is not always solution
for every problem, Cassandra + Mongo could be ;)
On Fri, Aug 17, 2012 at 7:54 PM, Aaron Turner synfina...@gmail.com wrote:
My stack:
Hi all,
This is the Cassandra mailing list, but I've developed something that is
strictly related to Cassandra, and some of you might find it useful, so
I've decided to send email to this group.
This is web based CQL3 editor. The idea is, to deploy it once and have
simple and comfortable CQL3
the cassandra-env.sh has option
JVM_OPTS=$JVM_OPTS -Xss180k
it will give this error if you start cassandra with java 7. So increase the
value, or remove option.
Regards,
Maciej
On Mon, Dec 16, 2013 at 2:37 PM, srmore comom...@gmail.com wrote:
What is your thread stack size (xss) ? try
Hi everybody,
I am aware that this mailing list is meant for Cassandra users, but I’ve
developed something that is strictly related to Cassandra, so I tough that it
might be interesting for some of you.
I’ve already sent one email several months ago, but since then a lot of things
has
thanks - I've fixed it.
Regards,
Maciej
On Mon, May 12, 2014 at 2:50 AM, graham sanderson gra...@vast.com wrote:
Looks cool - giving it a try now (note FYI when building,
TestDataConverter.java line 46 assumes a specific time zone)
On May 11, 2014, at 12:41 AM, Maciej Miklas mac.mik
missing something here?
Regards,
Maciej Miklas
/dev/blog/does-cql-support-dynamic-columns-wide-rows
-- Jack Krupansky
From: Maciej Miklas
Sent: Monday, May 19, 2014 11:20 AM
To: user@cassandra.apache.org
Subject: CQL 3 and wide rows
Hi *,
I’ve checked DataStax driver code for CQL 3, and it looks like the column
names
,
wide_row_column text,
data_column text,
PRIMARY KEY (row_key, wide_row_column));
Check out, for example,
http://www.datastax.com/dev/blog/schema-in-cassandra-1-1.
James
From: Maciej Miklas mac.mik...@gmail.com
Sent: Monday, May 19, 2014 11:20 AM
To: user@cassandra.apache.org
Subject: CQL 3 and wide
://www.thelastpickle.com
On 20/05/2014, at 8:18 am, Maciej Miklas mac.mik...@gmail.com wrote:
Hi James,
Clustering is based on rows. I think that you meant not clustering columns,
but compound columns. Still all columns belong to single table and are
stored within single folder on one computer
-
Aaron Morton
New Zealand
@aaronmorton
Co-Founder Principal Consultant
Apache Cassandra Consulting
http://www.thelastpickle.com
On 20/05/2014, at 8:18 am, Maciej Miklas mac.mik...@gmail.com wrote:
Hi James,
Clustering is based on rows. I think that you meant
Thank you Nate - now I understand it ! This is real improvement when compared
to CLI :)
Regards,
Maciej
On 20 May 2014, at 17:16, Nate McCall n...@thelastpickle.com wrote:
Something like this might work:
cqlsh:my_keyspace CREATE TABLE my_widerow (
... id text,
38 matches
Mail list logo
