[ottl] ParseTime should pre-convert from strptime to gotime format

[djaglowski]

Component(s)

pkg/ottl

Describe the issue you're reporting

Currently, the Time function runs timeutils.ParseStrptime for every string that needs to be parsed as a time.Time. This in turn calls ctimefmt.ToNative, which is doing a deterministic string replacement operation.

The OTTL function should instead call timeutils.StrptimeToGotime once at collector startup, and then call timeutils.ParseGotime during normal operations.

[djaglowski]

For context, ToNative was observed to be wasting ~5% of compute on a real world configuration.

[github-actions[bot]]

Pinging code owners:

• pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

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[github-actions[bot]]

Pinging code owners for pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley. See Adding Labels via Comments if you do not have permissions to add labels yourself.

[TylerHelmuth]

@djaglowski I'm interested in fixing this performance issue, but I don't see any connection to timeutils.ParseStrptime from ParseJSON.

I only see timeutils.ParseStrptime called from the Time converter. I suspect your proposal could be implemented there.

[djaglowski]

Sorry, I got some wires crossed looking at several issues at once. ParseJSON is not the function in question. It should read Time instead. I've now corrected the wording above.