/var/tmp in FailureDetector
I was reading through some code and noticed the following in
FailureDetector.dumpInterArrivealTimes()
FileOutputStream fos = new FileOutputStream("/var/tmp/output-" +
System.currentTimeMillis() + ".dat", true);
If this is meant to be cross platform I'm happy to create a bug and change it
to use File.createTempFile() .
Also I could not find any use of the dumpInterArrivalTimes(InetAddress ep)
overload. Anyone know if it should be kept?
thanks
Aaron
Would it be possible to do a ColumnCache?
Hi. Before wasting time in something that might not be feasible at the moment, I wanted to ask the devs if a column cache would be possible (instead of a whole row cache). This would allow users with fat rows to also use a cache and reduce latency for hot data. If this is possible, i'd appreciate some hints about where to dig. Thanks for your time!
Re: /var/tmp in FailureDetector
Yes, we should generate it in the right temp directory. That method
is an implementation of an interface method (FailureDetectorMBean),
meant to be invoked by JMX, which is why no other code calls it.
Gary.
On Wed, Oct 20, 2010 at 03:48, aaron morton wrote:
> I was reading through some code and noticed the following in
> FailureDetector.dumpInterArrivealTimes()
>
> FileOutputStream fos = new FileOutputStream("/var/tmp/output-" +
> System.currentTimeMillis() + ".dat", true);
>
> If this is meant to be cross platform I'm happy to create a bug and change it
> to use File.createTempFile() .
>
> Also I could not find any use of the dumpInterArrivalTimes(InetAddress ep)
> overload. Anyone know if it should be kept?
>
> thanks
> Aaron
>
>
Re: /var/tmp in FailureDetector
I should have mentioned the FailureDetectorMBean only has the parameterless
dumpInterArrivalTimes().
The overload that takes InetAddress is not available through JMX.
A
On 21 Oct 2010, at 01:55, Gary Dusbabek wrote:
> Yes, we should generate it in the right temp directory. That method
> is an implementation of an interface method (FailureDetectorMBean),
> meant to be invoked by JMX, which is why no other code calls it.
>
> Gary.
>
> On Wed, Oct 20, 2010 at 03:48, aaron morton wrote:
>> I was reading through some code and noticed the following in
>> FailureDetector.dumpInterArrivealTimes()
>>
>>FileOutputStream fos = new FileOutputStream("/var/tmp/output-" +
>> System.currentTimeMillis() + ".dat", true);
>>
>> If this is meant to be cross platform I'm happy to create a bug and change
>> it to use File.createTempFile() .
>>
>> Also I could not find any use of the dumpInterArrivalTimes(InetAddress ep)
>> overload. Anyone know if it should be kept?
>>
>> thanks
>> Aaron
>>
>>
Re: /var/tmp in FailureDetector
You're right! It looks like dead code that should be removed.
Gary.
On Wed, Oct 20, 2010 at 12:50, aaron morton wrote:
> I should have mentioned the FailureDetectorMBean only has the parameterless
> dumpInterArrivalTimes().
>
> The overload that takes InetAddress is not available through JMX.
>
> A
> On 21 Oct 2010, at 01:55, Gary Dusbabek wrote:
>
>> Yes, we should generate it in the right temp directory. That method
>> is an implementation of an interface method (FailureDetectorMBean),
>> meant to be invoked by JMX, which is why no other code calls it.
>>
>> Gary.
>>
>> On Wed, Oct 20, 2010 at 03:48, aaron morton wrote:
>>> I was reading through some code and noticed the following in
>>> FailureDetector.dumpInterArrivealTimes()
>>>
>>> FileOutputStream fos = new FileOutputStream("/var/tmp/output-" +
>>> System.currentTimeMillis() + ".dat", true);
>>>
>>> If this is meant to be cross platform I'm happy to create a bug and change
>>> it to use File.createTempFile() .
>>>
>>> Also I could not find any use of the dumpInterArrivalTimes(InetAddress ep)
>>> overload. Anyone know if it should be kept?
>>>
>>> thanks
>>> Aaron
>>>
>>>
>
>
Question about ColumnFamily Id's
I was helping a guy who in the end had a mixed beta1 and beta2 cluster http://www.mail-archive.com/u...@cassandra.apache.org/msg06661.htmlI had a look around the code and have a couple of questions, just for my understanding. When ReadResponseSerialize is called to deserialize the response from a node, it calls the RowSerializer which uses the ColumnFamilySerializer. If the CfId in the row is not known on the node a UnserializableColumnFamilyException is thrown. It's an IOException sub class and the error is treated as an Internal Error by the thrift generated Cassandra server. The read message sent to the node contains the Keyspace+CF names, and it returns it's CfID in the response. It looks like if a node somehow has a different/bad schema it can cause reads to fail. Is this correct? Could it's response be ignored if the read still meets the CL?Next question was how nodes could ever get to have a different CfId for the same Keyspace+CF pair? It looks like the the CfId is never changed, so it would only happen if two node were each given a schema update and could not communicate it with each other.Am guessing the whole scenario is "unsupported" just trying to understand whats happening. ThanksAaron
Re: /var/tmp in FailureDetector
Done in r1025822
On Wed, Oct 20, 2010 at 12:54 PM, Gary Dusbabek wrote:
> You're right! It looks like dead code that should be removed.
>
> Gary.
>
> On Wed, Oct 20, 2010 at 12:50, aaron morton wrote:
>> I should have mentioned the FailureDetectorMBean only has the parameterless
>> dumpInterArrivalTimes().
>>
>> The overload that takes InetAddress is not available through JMX.
>>
>> A
>> On 21 Oct 2010, at 01:55, Gary Dusbabek wrote:
>>
>>> Yes, we should generate it in the right temp directory. That method
>>> is an implementation of an interface method (FailureDetectorMBean),
>>> meant to be invoked by JMX, which is why no other code calls it.
>>>
>>> Gary.
>>>
>>> On Wed, Oct 20, 2010 at 03:48, aaron morton wrote:
I was reading through some code and noticed the following in
FailureDetector.dumpInterArrivealTimes()
FileOutputStream fos = new FileOutputStream("/var/tmp/output-"
+ System.currentTimeMillis() + ".dat", true);
If this is meant to be cross platform I'm happy to create a bug and change
it to use File.createTempFile() .
Also I could not find any use of the dumpInterArrivalTimes(InetAddress
ep) overload. Anyone know if it should be kept?
thanks
Aaron
>>
>>
>
--
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com
Re: Would it be possible to do a ColumnCache?
I don't think it's possible. Cassandra's data model means you can't know what columns are present in a row, so if you query, say, name and birthdate from your users column family and only the name column is in the cache for the row you are querying, does that mean that birthdate doesn't exist in that row? Or just that it's not cached? You don't know, so you'd have to do a full read every time. Similar difficulties arise with slices. 2010/10/20 Héctor Izquierdo Seliva : > Hi. Before wasting time in something that might not be feasible at the > moment, I wanted to ask the devs if a column cache would be possible > (instead of a whole row cache). This would allow users with fat rows to > also use a cache and reduce latency for hot data. > > If this is possible, i'd appreciate some hints about where to dig. > > Thanks for your time! > > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
