Azure/azure-functions-durable-extension

What is the Durable function "isolated" mode alternative for "extendedSessionsEnabled" ?

Shakeebmm opened this issue · 3 comments

Shakeebmm commented

I have a .NET 8 based "isolated" mode durable function which implements the fan out/fan in pattern.
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Expected F2 count is 100k activity function calls, which is getting executed in batch of 20 F2 calls.
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Delay between each batch getting increased along with the execution and function app memory also increasing consistently.
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This was resolved by enabling extendedSession in "in-proc" mode.. By enabling the extended session, 20 hours of execution was reduced to 1.5 hours.
{ "extensions": { "durableTask": { "extendedSessionsEnabled": true, "extendedSessionIdleTimeoutInSeconds": 30 } } }

But in "isolated" mode, extended sessions are not supported.
https://learn.microsoft.com/en-us/azure/azure-functions/durable/durable-functions-perf-and-scale#language-runtime-considerations
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What is the solution/work around in "isolated" mode?

davidmrdavid commented

Hi @Shakeebmm: Unfortunately, there's no direct equivalent of "extended sessions" in the isolated model yet. What's the performance difference you're seeing in the isolated mode?

Shakeebmm commented

Hi @davidmrdavid, There are 100k+ activity functions which are getting executed in batch of10 activities at a time.

Without extended session: gap between each batch getting increased. At the end of 100k activities, the gap is 3+ minutes. Orchestration trigger takes time to get the tracking details when the execution progress.

With extended session: Gap between each batch is consistent to couple of secs as the data is kept in session for 30 secs

davidmrdavid commented

Thank you @Shakeebmm. FYI @lilyjma, in case this factors in to our prioritization for next semester