amazon web services - IOPS limits on EC2 with EBS mounting -

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i had posted question on iops limit in ec2 instance not use ebs. question deals ec2 instance elastic block storage. environment goes -

  • two c4.8xlarge ec2 instances, 1 c4.8xlarge instance supports 500 mb/s throughput
  • connection pool 2049
  • got rid of dns cache
  • ebs storage of 120 gb each instance
  • application load tested jmeter 2.13 1 hour on distributed mode using 10 m4.4xlarge instance
  • test executed 700 threads ramp period of 30 mins , continues 700 threads 30 mins.
  • there 2 apis being load tested 1 has write operation (post request) , other had read operation (get request)
  • test reaches throughput of 7800 requests/sec read operation , 300 requests/sec write operation 400 threads , stays @ ~7800 requests/sec irrespective of threads increasing 700 threads.
  • following graphs of read , write throughput during tests ebs -

enter image description here enter image description here

  • and how average read , write size appear during test - enter image description here

considering graphs above safely assume not hit iops limit?

7800 requests per second. each request 4 kb read. so, total 31200 kb, around 31 mb/sec. write comes around 18 mb/sec per data. c4.8xlarge 500 mb per second max per this: ebs ec2 config.

the throughput depends on ebs volume size. current ratio 30:1 per: ebs iops:gb ratio.

so, 120 gb on c4.8xlarge, need 3600 mbps or 450 mb/sec.

also, did try increasing number of m4.4xlarge instances or using powerful m4.10x instances. may can bottleneck. cpu usage on these instances when tests running?


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