Use a set to keep track of metric ids for perf gains

[tzjames]

Features and Changes

Speeds up organization/definitions route for orgs with a lot of metrics by looking up the metrics in O(1) time.

Testing

Ran

curl 'http://localhost:3100/organization/definitions' \
  -H 'Authorization: Bearer TOKEN_COPIED_FROM_BROWSER \
  -H 'X-Organization: ORG_ID_COPIED_FROM_BROWSER'  > before.out

applied the change and ran it again piping it to > after.out.
Then did diff before.out after.out and saw it return nothing.

Then did some benchmarking:

wrk -t1 -c1 -d30s \
  -H 'Authorization: Bearer COPIED FROM BROWSER REQUEST' \
  -H 'X-Organization: COPIED FROM BROWSER REQUEST' \
'http://localhost:3100/organization/definitions'

Before:

Running 30s test @ http://localhost:3100/organization/definitions
  1 threads and 1 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency   425.98ms   59.91ms 778.62ms   94.29%
    Req/Sec     1.86      0.43     3.00     80.00%
  70 requests in 30.03s, 544.66MB read
Requests/sec:      2.33
Transfer/sec:     18.14MB

Using MetricId sets:

Running 30s test @ http://localhost:3100/organization/definitions
  1 threads and 1 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency   327.55ms   77.21ms 576.97ms   90.00%
    Req/Sec     2.77      0.86     5.00     86.67%
  30 requests in 30.03s, 233.43MB read
  Socket errors: connect 0, read 75314, write 5356, timeout 0
Requests/sec:      1.00
Transfer/sec:      7.77MB

[github-actions]

Your preview environment pr-2881-bttf has been deployed.

Preview environment endpoints are available at:

• https://growthbook-3000-pr-2881-bttf.growthbook.okteto.dev
• https://growthbook-3100-pr-2881-bttf.growthbook.okteto.dev