Jaan Paljasma | Tech Blog

Amazon announced new generation C3 instance types , which are compute optimized instances, available in 5 sizes: c3.large, c3.xlarge, c3.2xlarge, c3.4xlarge and c3.8xlarge with 2, 4, 8, 16 and 32 vCPUs respectively. C3 instances will provide you with the highest performance processors and the lowest price/compute performance compared to all other Amazon EC2 instances. C3 instances also feature Enhanced Networking and SSD-based instance storage . For C3 Instances, each vCPU is a hardware hyperthread from 2.8 GHz Intel Xeon E5-2680v2 (Ivy Bridge) processors. Setting up c3.large instance with SSDs When setting up instance, make sure you add both Instance Store volumes. Its up to you how you like to set up your root storage, For this example I opted for 16GB, 480 provisioned IOPS (you need to maintain 30:1 ratio): Testing the SSD speed Once set up and server launched, we can use 2nd 16GB SSD (mounted on /dev/sdc) for swap on new Amazon Linux instance c3.large # Tes...

MongoDB capped collections are great storing volatile information, like access and debug logs. If you need to monitor regular log file, you would probably type something like this in your command line: tail -f /var/log/access_log . Cool thing is that you can do the same with MongoDB capped collections : Capped collections are fixed-size collections that support high-throughput operations that insert, retrieve, and delete documents based on insertion order. Capped collections work in a way similar to circular buffers: once a collection fills its allocated space, it makes room for new documents by overwriting the oldest documents in the collection. Creating a capped collection is easy; so lets create capped collection named log and size of 16MB (the maximum size of BSON object if you did not know): mongo localhost/test > db.createCollection( "log", { capped: true, size: 16777216 } ) Capped collections act like any other collections, but they work in first-in-first-ou...

Amazon Web Services announced cross-zone load balancer, which supposed to further improve distribution of requests amongst all the instances behind the load balancer. If you enable cross-zone load balancing, you no longer have to worry that clients caching DNS information will result in requests being distributed unevenly, resulting more even load. I went ahead and tried it out myself. Enabling the Cross-Zone Load Balancing goes through the command line, you need to download and configure the tool on your computer before proceeding. Read the instructions how to download, install and configure ELB command line tools here . List all the load balancers: elb-describe-lbs Enable the cross-zone load balancing elb-modify-lb-attributes loadbalancer-id --crosszoneloadbalancing "enabled=true" Verifying: elb-describe-lb-attributes  loadbalancer-id  --headers CROSS_ZONE_LOADBALANCING  CROSS_ZONE_LOADBALANCING_ATTRIBUTE_VALUE CROSS_ZONE_LOADBALANCING  true ...

MongoDB University Offers Comprehensive Exams Worldwide NEW YORK, NY- Nov 6, 2013 - I am very glad to announce that I have earned certification as a MongoDB Certified DBA, Associate Level .  About a month ago, I was offered to try out MongoDB Certified DBA exam as part of a pilot project, invitations only. Before that, I successfully passed both M101 and M102P courses (well that was almost a year ago).  Invitations were sent to a selected group only, and only 150 first were given a chance to try that exam. It was thrilling to receive congratulating email in my inbox today, saying that I have successfully passed this quite difficult exam. Certificate number is 100-000-011 which indicates me being 11th in the world getting this (links to verify will be available little bit later). According to The 451 Group's analysis of LinkedIn® member profiles, MongoDB is the most popular NoSQL database and now accounts for 49 percent of all mentions of NoSQL technologies. The ...