Try loading build time ICU version.

[wscho77]

Calling dlopen() function multiple times from an unknown max version to find the ICU library makes performance degradation under heavy IO contention.
To avoid this situation, try loading first with the ICU version used at build time.

In our tests, it took up to 100ms under heavy IO contention.

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Issue Details

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Calling dlopen() function multiple times from an unknown max version to find the ICU library makes performance degradation under heavy IO contention.
To avoid this situation, try loading first with the ICU version used at build time.

In our tests, it took up to 100ms under heavy IO contention.

Author:	wscho77
Assignees:	-
Labels:	area-System.Globalization
Milestone:	-

[tarekgh]

This is wrong, this will prevent loading latest version if there are two ICU versions on the system. This scenario is possible.

CC @janvorli

[tarekgh]

I am closing it, feel free to send any question or thought we can consider. Thanks for trying.

[janvorli]

@wscho77 you can solve this by passing in an explicit version of the ICU by setting CLR_ICU_VERSION_OVERRIDE env variable. Then we would use that version as the first attempt.

[wscho77]

@wscho77 you can solve this by passing in an explicit version of the ICU by setting CLR_ICU_VERSION_OVERRIDE env variable. Then we would use that version as the first attempt.

Thank your comment.
We are also considering about using "CLR_ICU_VERSION_OVERRIDE".
But we are finding alternative method to set build time ICU version because different ICU version can be used for each platform.

@tarekgh @janvorli Would you accept introducing another override env variable that sets to use build time icu version?

[wscho77]

And shouldn't the environment variable name be changed to "DOTNET_ICU_VERSION_OVERRIDE"?