Beefy Boxes and Bandwidth Generously Provided by pair Networks
Problems? Is your data what you think it is?
 
PerlMonks  

Re: perl 5.36 and the for_list feature - a simple speed comparison

by duelafn (Parson)
on Jun 21, 2022 at 11:46 UTC ( #11144897=note: print w/replies, xml ) Need Help??


in reply to perl 5.36 and the for_list feature - a simple speed comparison

List::Util::pairmap would be an existing solution very similar to the new feature. It also seems to run quite quickly (but I can't compare it to for_list since I don't have a new-enough perl).

use List::Util qw/ pairmap /; sub a_pairmap { my $i; pairmap { $i += $b } @vals; return $i; }

Good Day,
    Dean

Replies are listed 'Best First'.
Re^2: perl 5.36 and the for_list feature - a simple speed comparison
by kcott (Archbishop) on Jun 21, 2022 at 21:30 UTC

    G'day Dean,

    "List::Util::pairmap would be an existing solution very similar to the new feature. It also seems to run quite quickly (but I can't compare it to for_list since I don't have a new-enough perl)."

    No problem. I have v5.36.0 installed. I added your code to the OP benchmark code.

    Mine starts as follows. Refer to "perl5360delta: use v5.36" for why I removed the strict and warnings pragmata.

    #!/usr/bin/env perl use v5.36; use List::Util qw /pairs pairvalues pairmap/;

    I then added:

    • say a_pairmap(); after the existing eight say statements.
    • a_pairmap     => \&a_pairmap, to the end of the cmpthese hashref.
    • Your sub a_pairmap { ... } verbatim, at the end of the script.

    I ran the benchmark five times. All results were pretty much the same; here's a median set:

    2500050000 2500050000 2500050000 2500050000 2500050000 2500050000 2500050000 2500050000 2500050000 Rate a_pairs_alias a_pairs h_each h_by_key h_for_list +h_vals a_pair_vals a_pairmap a_for_list a_pairs_alias 48.8/s -- -4% -67% -73% -83% + -90% -90% -92% -94% a_pairs 51.0/s 4% -- -66% -71% -82% + -90% -90% -91% -94% h_each 150/s 207% 193% -- -16% -47% + -69% -71% -74% -82% h_by_key 178/s 265% 249% 19% -- -37% + -64% -65% -69% -78% h_for_list 284/s 482% 457% 90% 59% -- + -42% -45% -51% -66% h_vals 490/s 903% 860% 227% 175% 72% + -- -5% -16% -41% a_pair_vals 513/s 951% 906% 243% 188% 81% + 5% -- -12% -38% a_pairmap 582/s 1091% 1041% 289% 226% 105% + 19% 13% -- -30% a_for_list 827/s 1594% 1521% 453% 364% 191% + 69% 61% 42% --

    In all runs, a_pairmap was second fastest; and, h_by_key was faster than h_each (which differs from the OP results).

    My environment:

    $ perl -v | head -2 | tail -1 This is perl 5, version 36, subversion 0 (v5.36.0) built for cygwin-th +read-multi $ uname -a CYGWIN_NT-10.0 titan 3.2.0(0.340/5/3) 2021-03-29 08:42 x86_64 Cygwin

    — Ken

      Thanks for this. Updated code and results are in 11144924.

Re^2: perl 5.36 and the for_list feature - a simple speed comparison
by swl (Vicar) on Jun 21, 2022 at 22:49 UTC

    Thanks for that. List::Util::pairmap is a good suggestion.

    Below is some updated code to add your array code and a hash variant. The results of three runs follow.

    The conclusions wrt pairmap are pretty much the same as those of kcott in 11144922. A point of difference is that h_by_key remains slower in my case.

    I wonder if there are differences due to the compiler used to build the perls or there's something cygwin vs linux. My system details are at the end.

    Edit - the original code used say a_pairmap() twice. kcott++ for noting.

    Rate a_pairs_alias a_pairs h_by_key h_pairmap h_each h +_pair_vals h_for_list h_vals a_pair_vals a_pairmap a_for_list a_pairs_alias 83.5/s -- -7% -13% -33% -34% + -41% -53% -79% -83% -84% -90% a_pairs 89.5/s 7% -- -6% -28% -29% + -37% -50% -78% -82% -83% -89% h_by_key 95.5/s 14% 7% -- -23% -25% + -33% -46% -76% -81% -81% -88% h_pairmap 125/s 49% 39% 30% -- -2% + -12% -30% -69% -75% -76% -85% h_each 127/s 52% 41% 33% 2% -- + -11% -29% -68% -74% -75% -84% h_pair_vals 142/s 70% 59% 49% 14% 12% + -- -20% -65% -71% -72% -82% h_for_list 178/s 113% 99% 86% 43% 41% + 25% -- -56% -64% -65% -78% h_vals 401/s 380% 348% 320% 222% 217% + 182% 125% -- -18% -22% -50% a_pair_vals 490/s 487% 448% 413% 294% 287% + 245% 175% 22% -- -4% -39% a_pairmap 512/s 513% 472% 436% 311% 304% + 260% 188% 28% 4% -- -36% a_for_list 804/s 863% 799% 742% 546% 535% + 466% 352% 101% 64% 57% -- Rate a_pairs_alias a_pairs h_by_key h_each h_pair_vals + h_pairmap h_for_list h_vals a_pair_vals a_pairmap a_for_list a_pairs_alias 73.2/s -- -17% -25% -31% -49% + -49% -54% -82% -85% -86% -91% a_pairs 87.7/s 20% -- -10% -17% -39% + -39% -45% -79% -82% -83% -89% h_by_key 97.0/s 33% 11% -- -8% -32% + -32% -39% -77% -81% -82% -88% h_each 106/s 44% 21% 9% -- -26% + -26% -34% -75% -79% -80% -87% h_pair_vals 143/s 96% 63% 47% 35% -- + -0% -11% -66% -71% -73% -82% h_pairmap 143/s 96% 63% 48% 36% 0% + -- -11% -65% -71% -73% -82% h_for_list 160/s 119% 83% 65% 52% 12% + 12% -- -61% -68% -70% -80% h_vals 415/s 467% 373% 328% 292% 190% + 189% 159% -- -17% -22% -48% a_pair_vals 498/s 581% 468% 413% 371% 248% + 248% 211% 20% -- -6% -38% a_pairmap 531/s 626% 506% 448% 403% 271% + 271% 231% 28% 7% -- -33% a_for_list 797/s 990% 809% 722% 654% 457% + 456% 398% 92% 60% 50% -- Rate a_pairs_alias a_pairs h_by_key h_each h_pairmap h +_pair_vals h_for_list h_vals a_pair_vals a_pairmap a_for_list a_pairs_alias 75.9/s -- -18% -29% -41% -41% + -52% -58% -77% -83% -86% -89% a_pairs 92.4/s 22% -- -13% -28% -29% + -41% -49% -72% -80% -82% -87% h_by_key 107/s 40% 16% -- -17% -18% + -32% -41% -67% -77% -80% -85% h_each 128/s 69% 39% 20% -- -1% + -18% -29% -60% -72% -76% -82% h_pairmap 130/s 71% 40% 21% 1% -- + -17% -28% -60% -72% -75% -82% h_pair_vals 157/s 106% 70% 47% 22% 21% + -- -13% -52% -66% -70% -78% h_for_list 180/s 137% 95% 69% 40% 39% + 15% -- -45% -61% -66% -74% h_vals 325/s 328% 252% 204% 153% 151% + 107% 80% -- -29% -38% -54% a_pair_vals 459/s 504% 397% 330% 257% 254% + 193% 155% 41% -- -13% -35% a_pairmap 527/s 594% 470% 394% 311% 306% + 236% 192% 62% 15% -- -25% a_for_list 705/s 828% 663% 560% 449% 444% + 350% 291% 117% 54% 34% --
    perl -v | head -2 | tail -1 This is perl 5, version 36, subversion 0 (v5.36.0) built for x86_64-li +nux uname -a Linux L-933C0F3 5.10.102.1-microsoft-standard-WSL2 #1 SMP Wed Mar 2 00 +:30:59 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux gcc -v 2>&1 | tail -2 Thread model: posix gcc version 9.4.0 (Ubuntu 9.4.0-1ubuntu1~20.04.1)

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://11144897]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others chilling in the Monastery: (5)
As of 2022-12-05 23:52 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found

    Notices?