Re: Slow libunwind performance with my build

[Borges, Matt]

Hi Dave,

 

Thanks a lot for the quick reply.  Your suggestion below worked 😊.

 

Thanks,

Matt

 

From: Dave Watson <dade.watson@gmail.com>
Date: Monday, March 15, 2021 at 6:22 PM
To: Matt Borges <matt.borges@sap.com>
Cc: "libunwind-devel@nongnu.org" <libunwind-devel@nongnu.org>
Subject: Re: Slow libunwind performance with my build

 

Probably a configure flag, try some combination of

 

--disable-debug

--disable-block-signals

--disable-conservative-checks

--enable-per-thread-cache

 

On Mon, Mar 15, 2021 at 3:17 PM Borges, Matt <matt.borges@sap.com> wrote:

Hi,

 

Sorry if this gets sent twice...

 

I grabbed the 1.5.0 source and built libunwind myself on a linux SUSE system.  On this linux machine there already exists libunwind in /usr/lib64 but I want to build it myself.  To build I’m running autogen.sh, then configure and finally make.  When I run my test program which gets callstacks once a millisecond, I see that the libunwind I built takes 4 times longer than the one installed on the system.

 

I’ve also tried adding -O2 -m64 to CFLAGS and CXXFLAGS but it doesn’t make a difference.

 

Is there anything obvious in the above steps that would indicate why there is this huge difference in performance with the version I am building?  For example, do I have to pass any options to autogeh.sh, configure, or make to perform an optimized production build?

 

Thanks in advance,

Matt

--

-Dave