codecov[bot]
commented
2 years ago Codecov Report
Merging #3462 (1f31dc4) into master (88fc9c1) will decrease coverage by
0.04%. The diff coverage is78.26%.
@@ Coverage Diff @@
## master #3462 +/- ##
==========================================
- Coverage 81.05% 81.01% -0.05%
==========================================
Files 421 424 +3
Lines 32205 32337 +132
==========================================
+ Hits 26105 26198 +93
- Misses 6100 6139 +39 | Impacted Files | Coverage Δ | |
|---|---|---|
| src/inbox/mod_inbox_rdbms.erl | 93.54% <ø> (-0.17%) |
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| src/wpool/mongoose_wpool.erl | 83.17% <55.55%> (-2.54%) |
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| src/async_pools/mongoose_aggregator_worker.erl | 61.70% <61.70%> (ø) |
|
| src/rdbms/mongoose_rdbms.erl | 63.63% <66.66%> (+0.34%) |
:arrow_up: |
| src/inbox/mod_inbox_rdbms_async.erl | 67.24% <67.24%> (ø) |
|
| src/rdbms/rdbms_queries.erl | 88.11% <80.00%> (-0.43%) |
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| src/mam/mod_mam_muc_rdbms_arch_async.erl | 82.85% <82.85%> (ø) |
|
| src/async_pools/mongoose_async_pools.erl | 91.66% <91.66%> (ø) |
|
| src/async_pools/mongoose_batch_worker.erl | 67.30% <100.00%> (ø) |
|
| src/inbox/mod_inbox.erl | 88.29% <100.00%> (+0.25%) |
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| ... and 9 more |
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NelsonVides
mongoose-im
Updated 22/02/2022
TODO:
How is it done:
A worker pool selects the worker using the
hash_workerstrategy, on the inbox entry key. This way, a single worker will be responsible for dealing with all the events for this key, being therefore able to ensure linearisation, and not only but also to aggregate them. That is, two incoming messages, instead of doing two DB operations with two +1 increments, can instead aggregate the increments and do a single DB operation at the end.Then, we use the new
gen_server:send_request/2https://www.erlang.org/doc/man/gen_server.html#send_request-2, that in all effects behaves just like a gen_server:call, except that instead of blocking until an answer or timeout, it returns an opaque reference that can later be used to verify an answer, using https://www.erlang.org/doc/man/gen_server.html#check_response-2. This way, if the DB pool is overloaded, the inbox worker can just continue aggregating entries, and will submit flushes to the DB only one at a time, finding a very good producer-consumer balance.