Skip to main content

abnormal data migration

Cloud storage is a funny and interesting field.  Just analyzed one data pattern where one customer sent a 4 TB hard drive and just migrating 1.2TB of it into cloud created 5M files.  Doing some rough calculation the avg size came out to be 300KB,  which is weird.  Digging deep into the system revealed that the customer scanned all his documents into TIF and the avg size ranged from 10KB to 100KB to 300KB.  wth.

Also they had a special LFT or loft file that was 4112 bytes and 2M of them were there.

As of right now the sharding approach I had implemented, pins a customer to a shard and that means if we migrate the entire 4TB we would end up with 30M+ files. Life is going to be interesting in next few months.

It seems the solution I did an year back is already reaching limits and I need some other solution to federate a customer data across multiple shards and machines but still able to do a consistent mysql backup and replication and also do a 2 phase commit across multiple servers.

or we put some arbitary limit on no of files in a domain and give them multiple domains to put data into it (which doesnt sound good).

Comments

Post a Comment

Popular posts from this blog

RabbitMQ java clients for beginners

Here is a sample of a consumer and producer example for RabbitMQ. The steps are Download Erlang Download Rabbit MQ Server Download Rabbit MQ Java client jars Compile and run the below two class and you are done. This sample create a Durable Exchange, Queue and a Message. You will have to start the consumer first before you start the for the first time. For more information on AMQP, Exchanges, Queues, read this excellent tutorial http://blogs.digitar.com/jjww/2009/01/rabbits-and-warrens/ +++++++++++++++++RabbitMQProducer.java+++++++++++++++++++++++++++ import com.rabbitmq.client.Connection; import com.rabbitmq.client.Channel; import com.rabbitmq.client.*; public class RabbitMQProducer { public static void main(String []args) throws Exception { ConnectionFactory factory = new ConnectionFactory(); factory.setUsername("guest"); factory.setPassword("guest"); factory.setVirtualHost("/"); factory.setHost("127.0.0.1"); factory.se...
23 comments
Read more

Jersey streaming binary data

In the previous post I showed how you can post binary data to a jersey REST api. You can also use Jersey to serve files, although its better done by apache or nginx but sometimes you might want to serve thumbnails stored in a database out of a service and put varnish in front of the REST api to cache the thumbnails. This is just a demonstration of using jersey to serve binary data in streaming fashion. @Path("/download-service") public class DownaloadService extends SecureRestService { private static final AppLogger logger = AppLogger.getLogger(DownaloadService.class); @POST @Produces(MediaType.APPLICATION_OCTET_STREAM) public StreamingOutput getThumbnail( @FormParam("securityKey") final String securityKey, @FormParam("guid") final String guid) throws JSONException { return new StreamingOutput() { @Override public void write(OutputStream out) throws IOException { try { if (!isAuthorized(securityKey)) { response.sendErro...
12 comments
Read more

Spring 3.2 quartz 2.1 Jobs added with no trigger must be durable.

I am trying to enable HA on nodes and in that process I found that in a two test node setup a job that has a frequency of 10 sec was running into deadlock. So I tried upgrading from Quartz 1.8 to 2.1 by following the migration guide but I ran into an exception that says "Jobs added with no trigger must be durable.". After looking into spring and Quartz code I figured out that now Quartz is more strict and earlier the scheduler.addJob had a replace parameter which if passed to true would skip the durable check, in latest quartz this is fixed but spring hasnt caught up to this. So what do you do, well I jsut inherited the factory and set durability to true and use that public class DurableJobDetailFactoryBean extends JobDetailFactoryBean {     public DurableJobDetailFactoryBean() {         setDurability(true);     } } and used this instead of JobDetailFactoryBean in the spring bean definition     <bean i...
7 comments
Read more