Re: get_slice and deletes

Thanks, I thought as much. Will give it a clean out and see how it goes. AaronOn 14 Sep, 2010,at 03:40 PM, Jonathan Ellis wrote:On Mon, Sep 13, 2010 at 9:35 PM, Aaron Morton wrote: > Could a high level of deletes on a row reduce the get_slice performance ? absolutely. > Is > it worth forcing th

UnicodeEncodeError: 'ascii' codec can't encode character u'\u2122' in position 79: ordinal not in range(128)

hi, I am using pycass with cassandra 0.6.3 and encountered this error while inserting a column. The offending characters are in a column value. Could anyone shed some light on this issue? UserAgent: UnkownUA Referer: Traceback (most recent call last): File "../application/model/status2.py",

Re: get_slice and deletes

On Mon, Sep 13, 2010 at 9:35 PM, Aaron Morton wrote: > Could a high level of deletes on a row reduce the get_slice performance ? absolutely. > Is > it worth forcing the tombstones out by reducing the GCGraceSeconds and doing > a compaction to see what happens ? You can try it to verify, but tha

Re: Error when compile pelops

2.2.1. I'll try the cassandra.jar from the link you give and try again. On Mon, Sep 13, 2010 at 11:19 PM, Dan Washusen wrote: > I just downloaded the jar file in question and it seems fine... > >> wget -O cassandra.jar >> http://github.com/s7/mvnrepo/raw/master/org/apache/cassandra/cassandra/0.7

Re: Error when compile pelops

I just downloaded the jar file in question and it seems fine... > wget -O cassandra.jar > http://github.com/s7/mvnrepo/raw/master/org/apache/cassandra/cassandra/0.7.0-2010-09-12_19-23-07/cassandra-0.7.0-2010-09-12_19-23-07.jar&&; > unzip -t cassandra.jar Which version of Maven are you using? O

Error when compile pelops

I download the pelops source frm github , then cd the pelops folder. mvn compile But the error occurs. INFO] Compilation failure error: error reading /root/.m2/repository/org/apache/cassandra/cassandra/0.7.0-2010-09-12_19-23-07/cassandra-0.7.0-2010-09-12_19-23-07.jar; error in opening zip fil

get_slice and deletes

I'm running the 0.7 nightly build from aug 31 and noticed some different performance characteristics when using get_slice against a row that has seen a lot of deletes.One row in the key space has around 650K columns, colums are small at around 53 bytes each so a total of around 30MB. In the last ho

Re: Monitoring with Cacti

Cloudkick does monitor JMX now. That + custom alerts is pretty powerful. I work for Cloudkick, btw On Sun, Sep 12, 2010 at 9:39 AM, Dave Viner wrote: > I haven't tried cacti, but I'm using CloudKick as an external service for > monitoring Cassandra. It's super easy to get setup. Happy to sha

Re: Implementing locks using cassandra only

Sorry, another thought was when storing in the Number CF how about using the the number as the column name and the client ID as the column value. That way you could do a slice to get the highest number, and the client can still assemble the hash of client_id to number. AaronOn 14 Sep, 2010,at 10:46

Re: Couple of cache related questions

On Sun, Sep 12, 2010 at 6:10 PM, kannan chandrasekaran wrote: >> 1) What determines the amount of memory used per schema ignoring the >> general >> overhead to get cassandra up and running?  Is it just the size of the >> caches >> for the column Family + the memtable size ? > > and the bloom filte

Re: RE: Monitoring with Cacti

Will take another look to see what I can "borrow".ThanksAaronOn 14 Sep, 2010,at 03:53 AM, Jeremiah Jordan wrote: Have you checked out the munin scripts?  If you want a starting point for something that pulls data out of jmx and prints it out (so you can catch and graph it).  It is ver

Re: Implementing locks using cassandra only

Thanks for the post it looks really handy. I found this page to help my simple mind understand whats going on http://nob.cs.ucdavis.edu/classes/ecs150-1999-02/sync-bakery.html  I've got some thoughts / questions mostly about implementation...1. Any thoughts on how it would work with a dynamic numbe

Re: Implementing locks using cassandra only

Bakery algorithm is really interesting -- AFAIK it's the only mutex algorithm that doesn't assume an existing atomic operation like CAS. On Mon, Sep 13, 2010 at 11:46 AM, Thorsten von Eicken wrote: > I've been musing about how to implement locks using just cassandra, i.e. > without sql db or zook

Implementing locks using cassandra only

I've been musing about how to implement locks using just cassandra, i.e. without sql db or zookeeper. I wrote up what I've come up with on the wiki (it's a bit too long for an email) at . I'm wondering whether I've overlooked something, especially I'm n

RE: Monitoring with Cacti

Have you checked out the munin scripts? If you want a starting point for something that pulls data out of jmx and prints it out (so you can catch and graph it). It is very easy to setup this to get any jmx value you want. http://github.com/jamesgolick/cassandra-munin-plugins __

Re: buggy secondary indexes?

this is fixed in current trunk. On Mon, Sep 13, 2010 at 8:18 AM, Wayne wrote: > This is a use case we have been struggling with for a long time. How do we > maintain indexes? It is easy to write out a secondary index even manually, > but how does one maintain and index when a value changes. Our o

Re: buggy secondary indexes?

This is a use case we have been struggling with for a long time. How do we maintain indexes? It is easy to write out a secondary index even manually, but how does one maintain and index when a value changes. Our only scalable answer has been background processes that churn through everything to ver

Re: buggy secondary indexes?

OK, I'll try it, but this: "recreate user with different email, then finding user by original email returns again that updated user" --> remove user "user" && insert new user: "user":{"email":"ot...@email.com "} doesn't crash on thrift, it seems to be cassandra issue. Petr On Mon, Sep 13, 2010

Re: Cassandra & Pig

Hi did you register cassandra jars with Pig. This seems like a class loading problem. aj On Sep 10, 2010, at 3:38 AM, Mark wrote: Does anyone know of any good tutorials for using Pig with Cassandra? I am trying do a basic load: rows = LOAD 'cassandra://Foo/Bar' USING CassandraStorage();

Re: buggy secondary indexes?

Sounds like you may need to patch your php thrift See http://www.softwareprojects.com/resources/programming/t-php-thrift-library-for-cassandra-1982.html On 9/13/2010 5:09 AM, Petr Odut wrote: Hi, let's have CF User with indexed column email. Now i insert new user: "user":{"email":"s...@emai

buggy secondary indexes?

Hi, let's have CF User with indexed column email. Now i insert new user: "user":{"email":"s...@email.com"} finding user by email address by get_indexed_slices ... everything works all right updating email value (via batch_mutate) ends with TTransportException (TSocket: timed out reading 4 bytes f