Lamda is a cool server-less method to run functions. A warm java/jvm function that is simple can return in 1ms, this is A-MA-ZING However, a cold-start for JVM can sometimes take quite a while, especially if you do a ton of init. This is not the fault of JVM being crap, you have way too much init going on.
- Spring
- Initializing lots of services
/gradlew clean build
Create a JVM lambda with handler: com.longsight.Hello::myHandler
Deploy build/distributions/hello.zip to Lambda
Deploy this, click test, and get output of:
"ColdStart (zrjhu) took:1749 ms to get region"
And the logs have more details, including our StopWatch.
START RequestId: ee9aa55d-fcf4-11e5-8f2a-eb1e21b442fb Version: $LATEST
0(zrjhu)StopWatch 'Performance of com.amazonaws.regions.Region.getRegion': running time (millis) = 1749
-----------------------------------------
ms % Task name
-----------------------------------------
01749 100% Region.getRegion(Regions.US_EAST_1)
00000 000% Regions regions = Regions.fromName(us-west-2);
00000 000% Region.getRegion(regions);
Apr 07, 2016 7:14:23 PM com.longsight.Hello myHandler
INFO: lambdaHello instance(zrjhu) usage numbers: 0
END RequestId: ee9aa55d-fcf4-11e5-8f2a-eb1e21b442fb
REPORT RequestId: ee9aa55d-fcf4-11e5-8f2a-eb1e21b442fb Duration: 1829.58 ms Billed Duration: 1900 ms
Why does Region.getRegion(Regions.US_EAST_1) take 1.5s+ ?
Actually I don't want to know why it takes 1.5s, I just want a way for it to complete in 0ms from cold start.