14 karma · joined March 23, 2015
You can open a pretty complicated large DAG in and right away you’ll understand the data flow and processing steps. If you were to do similar in code, it becomes a lot harder unless you comply to good modular design practices.
This is also why common game engine and 3d rendering tools come with a UI for flow driven scripting. It’s intuitive and much easier to organize.
From the list of bad practices you've "seen" people do in SQL, I would guess their comfort zone code is probably a hot mess as well.
I did thorough testing of Memsql two years ago but went with Aurora instead. Would love to see how the product evolved since (Spark and Streaming integration was just being rolled out at the time), but something tells me pricing will be a deal breaker.
on a 100 node cluster i had roughly 500GB on each node. this was not a single index, multiple indexes, with roughly 8 shards per index per node. Shard count is pretty important to get correct.
I did not manually control document routing (it was hard based on the type of data i was ingressing), so it was set to auto and during the load i observed hotspots in the cluster (you have to look at BULK thread/queue length), some nodes were getting burst of docs while others were idle, roughly 40-50% of the nodes in the cluster were under utilized, and maybe 5-10% had hot spots from time to time.
Also, depending what you use to push data in, (I used ES hadoop plugin) , you have to account for shard segment merges, which literally pause ingress for a brief moment and merge segments in a given shard. You have to set retry to -1 (infinite) and retry delay to something like a second or two, otherwise you will end up with dropped documents.
basically if you want fast ingress, keep shards small, once they get past ~5-10gb , ingress significantly slows down. Also this was on ES 1.5 , have not tested latest 2.0+ builds
Postgres has been a pain as described in the article.......