[rrd-users] rrdtool cluster filesystem question

[Simone Caruso]

On 28/12/2011 15:43, Francesco Andreozzi wrote:
> hi all,
> I have a question....
> Actually we use one machine to process lot of rrd data, we use rrdcached
> to works and everything works great.
> 
> We works on a debian machine with a precompiled rrdtool 1.4.3 package.
> Due to the heavy load of the server and redundancy requirement we need
> to enable a cluster to manage our application and work on rrd files.
> 
> We try to share the data via NFS in order to be able to made read and
> write operation on multiple nodes... but this seems to not works... we
> saw a lot of messages about locking problem and all the data still NaN.
> 
> We search on the list and found informations about compiling option
> without mmap feature.
> 
> I dont know exactly what mmap do but what i understand this feature
> speedup read and write process because reduce disk access time....
> 
> Ok but my question is...
> 
> NFS can be a good solution or i have to move on cluster FS like OCFS2?
> 
> if i can use NFS what feature i need to disable/enable to have rrdtool
> and rrdcached working good?
> 
> What are the performance difference if i use MMAP or not ?
> 
> Thankyou a lot
> Francesco
> 

It's not a good idea concurrent I/O on the same file from multiple applications,
u should write a application level lock. Maybe GFS2/OCFS2 + DBRBD can help you.


-- 
Simone Caruso
IT Consultant
+39 349 65 90 805