3 ms·
I went and run a ping between 2 VMs, one on us-east1c and the other on a different AZ - us-east-1b As you can see, the ping latency is 0.5ms to 1ms on rare occ
by thekozmo 8y ago
I went and run a ping between 2 VMs, one on us-east1c and the other on a different AZ - us-east-1b
As you can see, the ping latency is 0.5ms to 1ms on rare occasions. Of course that ping has a cost even within a single AZ so the above numbers reflect much more than the AZ round trip time.
You're welcome to add 1ms to our latency numbers, it's 3x-4x better in the 99th case so there's enough room...
64 bytes from 35.173.249.24: icmp_seq=14 ttl=63 time=0.584 ms
64 bytes from 35.173.249.24: icmp_seq=15 ttl=63 time=0.462 ms
64 bytes from 35.173.249.24: icmp_seq=16 ttl=63 time=0.848 ms
64 bytes from 35.173.249.24: icmp_seq=17 ttl=63 time=0.465 ms
64 bytes from 35.173.249.24: icmp_seq=18 ttl=63 time=0.451 ms
64 bytes from 35.173.249.24: icmp_seq=19 ttl=63 time=1.00 ms
64 bytes from 35.173.249.24: icmp_seq=20 ttl=63 time=0.854 ms
64 bytes from 35.173.249.24: icmp_seq=21 ttl=63 time=0.446 ms
- erik_seaberg 8y agoInter-AZ latency is going to matter more for conditional writes. I'm disappointed to find LWT so far out on Scylla's roadmap since preventing conflicts is a showstopper for correctness and we found it to be Cassandra's weak point in scaling.
- jjirsa 8y agofwiw, work being done on Cassandra to speed this (cas/lwt) up SIGNIFICANTLY
- ddorian43 8y agoLink ?
- jjirsa 8y agoStarted here: https://lists.apache.org/thread.html/15d1b4b5bb8a24e41d51db58538b56d0bab40c17fc9c64e898f2ad3b@%3Cdev.cassandra.apache.org%3E https://lists.apache.org/thread.html/15d1b4b5bb8a24e41d51db5... Continues here: https://issues.apache.org/jira/browse/CASSANDRA-14448 https://issues.apache.org/jira/browse/CASSANDRA-14448