Thanks Vladimir !!
The drawback with using HDFS as persistent store behind Ignite cache is how we 
will take care of appending single key value pair to HDFS file.Ideally we 
should use some NoSQL store or RDBMS as persistent back up behind Ignite cache 
and then run some scheduled batch to transfer the data to HDFS as it happens in 
normal Lambda Architecture.
Now question comes why we want to use Ignite Cache ? Answer is it gives SQL 
interface that means we can query on any attribute on the fly.Other we could 
have used any other NoSQL. But NoSQL data model is entirely based upon query 
pattern so to bring the flexibility at the time of query we think Ignite cache 
would be better.
For our use case we want to put the latest 2 week data in Ignite cache to meet 
the latency requirements and then for any back date get the data from backend 
persistent storage, for which we are thinking about HDFS.Thats why we were 
thinking if we can make Ignite cache write through cache with HDFS as backed up 
persistent storage it would serve the purpose.
Please let me know whats your view on this. 
Many thanks,Vij 

    On Wednesday, April 13, 2016 8:58 PM, Vladimir Ozerov 
<voze...@gridgain.com> wrote:
 

 Vij,
No, it doesn't. IGFS serves the very different purpose - it is 
Hadoop-compatible file system. It means that, for example, you can load data to 
IGFS and then query it using Hive. But native Ignite SQL is not applicable here.
Vladimir.
On Wed, Apr 13, 2016 at 3:55 PM, vijayendra bhati <veejayend...@yahoo.com> 
wrote:

Thanks Vladimir,
I have not gone through complete documentation but if you could let me know 
does IGFS provide SQL support like Ignite cache does ?
Regards,Vij 

    On Wednesday, April 13, 2016 5:54 PM, Vladimir Ozerov 
<voze...@gridgain.com> wrote:
 

 Hi Vijayendra,
IGFS is designed to be a distributed file system which could cache data from 
Hadoop file systems. It cannot be used as cache store by design.Ignite doesn't 
have store implementation for HDFS, so you should implement your own if needed. 
Particularly, you should implement org.apache.ignite.cache.store.CacheStore 
interface.
Vladimir.
On Wed, Apr 13, 2016 at 2:38 PM, vijayendra bhati <veejayend...@yahoo.com> 
wrote:

Hi,
Can some body please provide me any pointers regarding how I can use Ignite 
Data Grid/ In Memory caching with write through/write behind mode and writing 
to HDFS ?
I know Ignite provides IGFS but its different from what I am looking for.
The other way could be I can use IGFS as my In Memory store but is it the right 
approach ?
Regards,Vijayendra Bhati



   



  

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