Use 'try'/'catch' rather than 'ets:whereis/1' for Khepri projections #11700
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`ets:whereis/1` adds some overhead - it's two ETS calls rather than one when `ets:whereis/1` returns a table identifier. It's also not atomic: the table could disappear between `ets:whereis/1` calls and the call to read data from a projection. We replace all `ets:whereis/1` calls on projection tables with `try`/`catch` and return default values when we catch the `badarg` `error` which ETS emits when passed a non-existing table name. One special case though is `ets:info/2` which returns `undefined` when passed a non-existing table names. That block is refactored to use a `case` instead.
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Good point about the overhead @dumbbell I'm not so worried about tables disappearing but who knows! |
michaelklishin
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Jul 12, 2024
the-mikedavis
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Use 'try'/'catch' rather than 'ets:whereis/1' for Khepri projections (backport #11700)
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See #11667 (comment)
ets:whereis/1adds some overhead - it's two ETS calls rather than one whenets:whereis/1returns a table identifier. It's also not atomic: the table could disappear betweenets:whereis/1calls and the call to read data from a projection. We replace allets:whereis/1calls on projection tables withtry/catchand return default values when we catch thebadargerrorwhich ETS emits when passed a non-existing table name.One special case though is
ets:info/2which returnsundefinedwhen passed a non-existing table names. That block is refactored to use acaseinstead.