[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: GLPSOL in webassemby faster than native ?

From: Domingo Alvarez Duarte
Subject: Re: GLPSOL in webassemby faster than native ?
Date: Tue, 22 Sep 2020 18:17:21 +0200
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0

Hello Andrew !

In this case mean compiling with "-O3 -DNDEBUG -DWITH_SPLAYTREE" on Arm7, "-O3 -DNDEBUG -flto -march=native -ffp-contract=off -DWITH_SPLAYTREE" on x86_64 and "-O3 -DNDEBUG -flto -DWITH_SPLAYTREE" on wasm.

How are the parameters for the cut generations selected ?

Isn't strange that on wasm it's been faster than native ?

Doesn't this difference gives insight to select the parameter differently ?

Cheers !

On 22/9/20 17:56, Andrew Makhorin wrote:
On Tue, 2020-09-22 at 15:53 +0200, Domingo Alvarez Duarte wrote:
Hello again !

On an Android phone arm7 32bits Nexux-5 with chrome browser (wasm)
solving the "hashi.mod" with "--cuts" takes 98s and without it 909s,
using glpsol native compiled within termux takes 497s with "--cuts"
without it 925s.

What does "native" mean? Just changing, for example, optimization level
of the compiler may essentially change the set of generated cuts and
thus the solution time.

Arm7 32bits Nexus-5:

      wasm "--cuts -m hashi.mod" -> 98s

      wasm " -m hashi.mod" -> 909s

      native "--cuts -m hashi.mod" -> 497s

      native " -m hashi.mod" -> 925s

Laptop Linux 64bits I7:

      wasm "--cuts -m hashi.mod" -> 8s

      wasm " -m hashi.mod" -> 142s

      native "--cuts -m hashi.mod" -> 73s

      native " -m hashi.mod" -> 55s

On arm7 "--cuts" improves the performance in both wasm and native.

On x86_64 "--cuts" improves in wasm but degrade in native.

I hope this could give hints to improve GLPK solver performance by
inspecting the decision's criteria and eventually find a better ones.

Anyone can give any idea with this data ?

Cheers !

On 21/9/20 17:11, Andrew Makhorin wrote:
On Mon, 2020-09-21 at 16:09 +0200, Domingo Alvarez Duarte wrote:
Hello Andrew !

Are you saying that floating point calculations are more
efficient/precise in webassembly ?
No. I meant that due to floating-point computations running the same
computer program with the same data as a rule produces different
on different platforms.

Cheers !

On 21/9/20 15:08, Andrew Makhorin wrote:
Does someone can give a possible explanation ?
floating-point computations

reply via email to

[Prev in Thread] Current Thread [Next in Thread]