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Well, I don't know if anyone else has noticed this (maybe my mileage is way different) but when I tried timing a simple File::Find approach (as provided by "find2perl") against the equivalent back-tick `find ...` command on my linux box, I got a 5-to-1 wallclock ratio:
use strict; use Benchmark; use File::Find (); # this part is unnecessary, but find2perl made it up, so I copied it: use vars qw/*name *dir *prune/; *name = *File::Find::name; *dir = *File::Find::dir; *prune = *File::Find::prune; timethese( 10, { 'File::Find' => \&find2perl, 'Shell:Find' => \&shellfind, }); my @found; # I'm not using this for anything at present sub find2perl { @found = (); File::Find::find({wanted => \&wanted}, '.'); # made by find2perl } sub wanted { # made by find2perl my ($dev,$ino,$mode,$nlink,$uid,$gid); (($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($_)) && -d _ && push @found, $_; } sub shellfind { @found = `find . -type d`; } __END__ # OUTPUT: Benchmark: timing 10 iterations of File::Find, Shell:Find... File::Find: 27 wallclock secs (20.87 usr 4.01 sys + 0.01 cusr 0.00 +csys = 24.89 CPU) @ 0.40/s (n=10) Shell:Find: 5 wallclock secs ( 0.21 usr 0.01 sys + 1.28 cusr 3.36 +csys = 4.86 CPU) @ 45.45/s (n=10) # I printed scalar(@found) in one test, and these results # were obtained where there were over 6K directories under "."

So, maybe the first thing to try for speeding things up is:

# don't use File::Find;
Apart from that, have you considered an alternative like this:
  • run a separate process to create and maintain a set of file name listings for each path; the first time you run this, it'll take a long time, but thereafter, it only needs to find the directories that were created/modified since the last run, then for just those paths, diff the current file inventory against the previous file name list, and write the set of new files to a separate log file. (one approach is given below)
  • adapt your re-indexing job so that it works from the log of new files, and it doesn't use find at all.

Of course, you can put the two steps together into a single script.
#!/usr/bin/perl # Program: find-new-files.perl # Purpose: initialize and maintain a record of files in a # directory tree # Written by: dave graff # If a file called "paths.logged" does not exist in the cwd, we create # one, and treat all contents under cwd as "new". If "paths.logged" # already exists, we find directories with modification dates more # recent than this file, and treat only these as "new". # For each "new" directory, assume a file.manifest is there (create an # empty one if there isn't one), and diff that file against the curren +t # inventory of data files, storing all new files to an array. # Of course, this will fail in all paths where the current user does # not have write permission, but such paths can be avoided by adding # a suitable condition to the first "find" command. use strict; my $path_log = "paths.logged"; my ($list_name,$new_list) = ("file.manifest","new.manifest"); my $new_flag = ( -e $path_log ) ? "-newer $path_log" : ""; my @new_dirs = `find . -type d $new_flag`; # add "-user uname" and/or "-group gname" to avoid directories where # the current user might not have write permission my $diff_cmd = "cd 'THISPATH' && touch $list_name && ". "find . -type f -maxdepth 1 | tee $new_list | diff - $list_name | +grep '<'"; # the shell functions in $diff_cmd will: # - chdir to a given path, # - create file.manifest there if it does not yet exist, # - find data files in that path (not subdirs, not files in subdirs), # - create a "new.manifest" file containing this current file list, # - diff the new list of files against the existing file.manifest, # - return only current files not found in the existing manifest. # since it's a sub-shell, the chdir is forgotten when the sub-shell is + done. open( OUT, ">new-file-path.list" ); foreach my $path ( @new_dirs ) { chomp $path; my $cmd = $diff_cmd; $cmd =~ s{THISPATH}{$path}g; # the output of the shell command needs to be conditioned to have the # path string prepended to each file name (we can leave the new-line # in place at the end of the name): print OUT join "", map { s{^< \.(.*)}{$path$1}; $_ } ( `$cmd` ); # replace the old manifest: rename "$path/$new_list", "$path/$list_name" or warn "failed to update $path/$list_name\n"; } close OUT; `touch $path_log`;

update: fixed some commentary in the second program; realized that <br> is required after </ul>.

In reply to Re: File::Find redux: how to limit hits? by graff
in thread File::Find redux: how to limit hits? by 914

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