From 57bcca93b1ed1e31d8837ba1a43a872c9e4f757f Mon Sep 17 00:00:00 2001 From: Ben Sima Date: Tue, 23 Jan 2018 12:19:03 -0800 Subject: add readme --- readme.md | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 readme.md (limited to 'readme.md') diff --git a/readme.md b/readme.md new file mode 100644 index 0000000..31e0edf --- /dev/null +++ b/readme.md @@ -0,0 +1,23 @@ +1. Have [stack](http://haskellstack.org/) installed +2. Optional: have [nix](https://nixos.org/nix/) installed. If you *don't* use nix, delete line 3 of `main.hs`. +3. Run `./main.hs` and the server will startup + +To bootstrap the db, do `curl -XPOST "localhost:3000/bootstrap"`. + +This takes a while; on my machine it averages 181 records per second. It's IO +bound, and in an un-optimized program GHC on Linux uses a single, blocking IO +manager thread (on Windows it's non-blocking, [apparently][1]). This can be +improved with the [Control.Concurrent][1] module, it which case we could launch +as many IO threads as we want, and do probably 10k records per second. There's +definitely an optimal amount of threads here, we'd have to test to find that. + +*However*, you can watch it bootstrap. In a separate terminal, do `curl +"localhost:3000/count"` to see it updating. New POSTs will also work and update +the database, even while it is bootstrapping, which is kinda cool. + +Try this in bash: + + while sleep 1; do curl -s "localhost:3000/count" | jq '.count'; done + + +[1]: https://www.stackage.org/haddock/lts-10.3/base-4.10.1.0/Control-Concurrent.html#g:10 -- cgit v1.2.3