On 13 June 2010 18:54, Benjamin Black wrote:
> On Sun, Jun 13, 2010 at 12:53 AM, Torsten Curdt wrote:
> >
> > TBH while we are using super columns, the somehow feel wrong to me. I
> > would be happier if we could move what we do with super columns into
> > the row key space. But in our case tha
On 26 May 2010 22:56, Miguel Verde wrote:
> Right, in C# this would be (not the most efficient way, but you get the
> idea):
> long timestamp = (DateTime.Now.Ticks - new DateTime(1970, 1, 1).Ticks)/10;
>
>
> Yeah, you're fine provided:
a) All your client applications (which perform writes) are c
On 26 May 2010 22:42, Steven Haar wrote:
> What is the best timestamp to use while using Cassandra with C#? I have
> been using DateTime.Now.Ticks, but I have seen others using different
> things.
>
The standard that most clients seem to use is epoch-microseconds, or
microseconds since midnight
On 25 May 2010 09:04, David Boxenhorn wrote:
> I have seen several off-hand mentions that writes are inherently faster
> than reads. Why is this so?
>
In addition to the points that other posters made, writes only need to go as
far as your battery-backed raid controller, whereas reads go all the
On 23 May 2010 13:42, 史英杰 wrote:
> Hi, All
>I am now doing some tests on Cassandra, and I found that both writes and
> reads on 15 nodes are faster than that of 20 nodes, how many servers does
> one Cassandra system contains during the real applications?
>Thanks a lot !
>
> Yingjie
>
I'd
On 20 May 2010 23:16, Ryan Daum wrote:
> I personally would love to see Cassandra add the concept of a read-only
> 'proxy' node which acts like the embedded ready only mode (Java 'fat
> client') but sits as a stand alone server. It would know the the entire ring
> and watch Gossip and thus be abl
On 20 May 2010 20:17, David Wellman wrote:
> I have a 5 node cassandra cluster and I am wondering if there is any
> advantage of setting up a connection pool that is balanced across all 5
> nodes (IE: 50 connections = 10 per node) over one pool all to one server (50
> connection => one node)
De
>
> 2010/4/26 Roland Hänel :
> > Typically, in the SQL world we use things like AUTO_INCREMENT columns
> that
> > let us create a unique key automatically if a row is inserted into a
> table.
>
auto_increment is an antipattern; it adds an extra key which you don't need
(usually). If your data has
I can't see any advantage in using multiple keyspaces. It is highly unlikely
that several applications would share the same Cassandra cluster in any
nontrivial deployment.
Things more important than replication-factor, such as partitioner and ring
token distribution would be compromised by several
On 26 April 2010 01:18, 刘兵兵 wrote:
> i do some INSERT ,because i will do some scan operations, i use the
> OrderPreservingPartition method.
>
> the state of the cluster is showed below.
>
> as i predicated the load is very imbalance
I think the solution to this would be to choose your nodes' t
On 26 April 2010 00:57, Shuge Lee wrote:
> In Python:
>
> keyspace.columnfamily[key][column] = value
>
> files.video[uuid.uuid4()]['name'] = 'foo.flv'
> files.video[uuid.uuid4()]['path'] = '/var/files/foo.flv'
>
Hi.
Storing the filename in the database will not solve the file storage
problem. C
For me an important difference is that Cassandra is operationally much more
straightforward - there is only one type of node, and it is fully redundant
(depending what consistency level you're using).
This seems to be an advantage in Cassandra vs most other distributed storage
systems, which almos
On 25 April 2010 10:48, JKnight JKnight wrote:
> Dear all,
>
> My Cassandra server had thread leak when high concurrent load. I used
> jconsole and saw many, many thread occur.
>
Just because there are a lot of threads, need not imply a thread leak.
Cassandra uses a lot of threads.
Do you see t
>
> On Fri, Apr 16, 2010 at 1:28 PM, Linton N wrote:
>
>> hi ,
>> I am working for the past 1 year with hadoop, but quite new to
>> cassandra, I would like to get clarified few things regarding the
>> scalability of Cassandra. Can it scall up to TB of data ?
>>
>
TB of data is not really t
On 15 April 2010 02:42, Zhuguo Shi wrote:
> Hi,
>
> Cassandra has a good distributed model: decentralized, auto-partition,
> auto-recovery. I am evaluating about writing a file system over Cassandra
> (like CassFS: http://github.com/jdarcy/CassFS ), but I don't know if
> Cassandra is good at such
Can we not implement counts by just storing all the deltas in a row, and
then summing them all up to acheive a count.
If a row ends up with too many deltas, a reader could just summarise the
deltas occasionally into a single value (in a way which avoids race
conditions, of course).
So you'd map
On 11 April 2010 07:59, Lucifer Dignified wrote:
> For a very simple query wherin we need to check username and password I
> think keeping incremental numeric id as key and keeping the name and value
> same in the column family should work.
>
It is highly unlikely that your application has enou
On 7 April 2010 19:13, Jonathan Ellis wrote:
> One thing you can do is manually "randomize" keys for any CFs that
> don't need the OP by pre-pending their md5 to the key you send
> Cassandra. (This is all RP is doing under the hood anyway.)
>
Another possibility is to prepend some hash of somet
18 matches
Mail list logo
