Alexey Serbin has posted comments on this change.

Change subject: [rpc] faster generation of KRPC call ID
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Patch Set 2:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/7813/2//COMMIT_MSG
Commit Message:

PS2, Line 48:   const int u_bound = 800000000 + (random() % 100);
            :   int n = 0;
            :   for (int i = 0; i < u_bound; ++i) {
            :     n = next_id();
            :   }
> yea, if you compile in clang it turns it into a constant time operation. g+
Thank you for looking at this.

Just FYI: even with noinline, clang 3.5 with -O2 gives slightly better results 
on ve0518:

new:
  real    0m1.485s
  user    0m1.486s
  sys     0m0.000s

old:
  real    0m1.997s
  user    0m1.999s
  sys     0m0.001s

The fact that the function can be easily inlined and get better result is a 
good sign, IMO.  Especially given the fact we usually use clang++ to compile 
our binaries.
 
However, it's a minor thing and I agree it's not worth updating if the 
incentive to do so is low.


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Gerrit-MessageType: comment
Gerrit-Change-Id: I03726343d222bcd241c2c2a5a1670a672f8e5cb6
Gerrit-PatchSet: 2
Gerrit-Project: kudu
Gerrit-Branch: master
Gerrit-Owner: Alexey Serbin <[email protected]>
Gerrit-Reviewer: Adar Dembo <[email protected]>
Gerrit-Reviewer: Alexey Serbin <[email protected]>
Gerrit-Reviewer: Kudu Jenkins
Gerrit-Reviewer: Tidy Bot
Gerrit-Reviewer: Todd Lipcon <[email protected]>
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