2 posts tagged “ebs”
We have switched to an EBS deployment to make sure our databases are always backed up and can start a new EC2 instance very quickly from the EBS instance if needed. The first day into the switch, some transactions started performing poorly - from under 1 second to 20 seconds. When we compared the timings from the previous logs almost all transactions had a dip in performance from about double to 20 times.
What we noticed is a large number of small disk writes affects the whole disk performance, for read transactions as well. These writes are coming from log file entries - apache & tomcat logs. Once these are moved out of EBS the performance is back to normal and in some cases better than before. Looks like it is better to have a separate EBS instance for the database - database writes do not seem to have such adverse impact.
I did read about this a while back when the challenges using EC2 was how not lose a database in case of a machine failure. Luckily it never happened and forgot all about EBS, the persistent disk for Amazon EC2. We went live with a new customer over the weekend and EBS came up all over again for data backup. Quite simple to use it.
1. Created a new volume using ElasticFox and attached it to a running instance.
2. Formatted it to ext3 - yes | mkfs -t ext3 /dev/sdh
3. Created a new folder /permnt
4. Mounted it - mount /dev/sdh /permnt
5. That's all, it is up and running.
Its quite a pleasant experience using Amazon's various services - they are so simple to use which always inspires us startups to emulate that simplicity.
Still to check auto backup to S3 from EBS - I am sure it will be as simple.
