state of evolution. You should expect it to be very buggy. Do B<not> use
it for any purpose other than testing and development.
-To keep in sync with the most recent branch can be done in several
-ways, but the most convenient and reliable way is using B<rsync>,
-available at ftp://rsync.samba.org/pub/rsync/ (other ways include ftp).
+Keeping in sync with the most recent branch can be done in several ways,
+but the most convenient and reliable way is using B<rsync>, available at
+ftp://rsync.samba.org/pub/rsync/ . (You can also get the most recent
+branch by FTP.)
If you choose to keep in sync using rsync, there are two approaches
-to do so:
+to doing so:
=over 4
=item rsync'ing the source tree
-Presuming you are in the directory where your perl source resides,
+Presuming you are in the directory where your perl source resides
and you have rsync installed and available, you can `upgrade' to
the bleadperl using:
distribution) and setting date/time stamps of existing files to
reflect the bleadperl status.
+Note that this will not delete any files that were in '.' before
+the rsync. Once you are sure that the rsync is running correctly,
+run it with the --delete and the --dry-run options like this:
+
+ # rsync -avz --delete --dry-run rsync://ftp.linux.activestate.com/perl-current/ .
+
+This will I<simulate> an rsync run that also deletes files not
+present in the bleadperl master copy. Observe the results from
+this run closely. If you are sure that the actual run would delete
+no files precious to you, you could remove the '--dry-run' option.
+
You can than check what patch was the latest that was applied by
looking in the file B<.patch>, which will show the number of the
latest patch.
=item Using rsync over the LAN
Set up a local rsync server which makes the rsynced source tree
-available to the LAN, and sync the other machines towards this
+available to the LAN and sync the other machines against this
directory.
From http://rsync.samba.org/README.html:
"Rsync uses rsh or ssh for communication. It does not need to be
setuid and requires no special privileges for installation. It
- does not require a inetd entry or a deamon. You must, however,
+ does not require an inetd entry or a daemon. You must, however,
have a working rsh or ssh system. Using ssh is recommended for
its security features."
=item Using pushing over the NFS
Having the other systems mounted over the NFS, you can take an
-active pushing approach, in checking the just updated tree against
-the other not-yet synced trees. An example would be:
-
- ...... Xsync
-
-Though this is not perfect. It could be improved with checking
+active pushing approach by checking the just updated tree against
+the other not-yet synced trees. An example would be
+
+ #!/usr/bin/perl -w
+
+ use strict;
+ use File::Copy;
+
+ my %MF = map {
+ m/(\S+)/;
+ $1 => [ (stat $1)[2, 7, 9] ]; # mode, size, mtime
+ } `cat MANIFEST`;
+
+ my %remote = map { $_ => "/$_/pro/3gl/CPAN/perl-5.7.1" } qw(host1 host2);
+
+ foreach my $host (keys %remote) {
+ unless (-d $remote{$host}) {
+ print STDERR "Cannot Xsync for host $host\n";
+ next;
+ }
+ foreach my $file (keys %MF) {
+ my $rfile = "$remote{$host}/$file";
+ my ($mode, $size, $mtime) = (stat $rfile)[2, 7, 9];
+ defined $size or ($mode, $size, $mtime) = (0, 0, 0);
+ $size == $MF{$file}[1] && $mtime == $MF{$file}[2] and next;
+ printf "%4s %-34s %8d %9d %8d %9d\n",
+ $host, $file, $MF{$file}[1], $MF{$file}[2], $size, $mtime;
+ unlink $rfile;
+ copy ($file, $rfile);
+ utime time, $MF{$file}[2], $rfile;
+ chmod $MF{$file}[0], $rfile;
+ }
+ }
+
+though this is not perfect. It could be improved with checking
file checksums before updating. Not all NFS systems support
reliable utime support (when used over the NFS).
yourself to the source files.
Presuming you are in a directory where your patches reside, you can
-get them in sync with:
+get them in sync with
# rsync -avz rsync://ftp.linux.activestate.com/perl-current-diffs/ .
This makes sure the latest available patch is downloaded to your
patch directory.
-It's then up to you to apply these patches, using something like:
+It's then up to you to apply these patches, using something like
# last=`ls -rt1 *.gz | tail -1`
# rsync -avz rsync://ftp.linux.activestate.com/perl-current-diffs/ .
"... The rsync mirror is automatic and syncs with the repository
every five minutes.
- Updating the patch area still requires manual intervention
+ "Updating the patch area still requires manual intervention
(with all the goofiness that implies, which you've noted) and
is typically on a daily cycle. Making this process automatic
is on my tuit list, but don't ask me when."
=item It's more reliable
-Well, since the patches are updated by hand, I don't have to say no
+Well, since the patches are updated by hand, I don't have to say any
more ... (see Sarathy's remark).
=back
=item It's easier
If you have more than one machine that you want to keep in track with
-bleadperl, it's easier to rsync the patches only once and than apply
+bleadperl, it's easier to rsync the patches only once and then apply
them to all the source trees on the different machines.
In case you try to keep in pace on 5 different machines, for which
only one of them has access to the WAN, rsync'ing all the source
-tree's should than be done 5 times over the NFS, whereas having
+trees should than be done 5 times over the NFS. Having
rsync'ed the patches only once, I can apply them to all the source
-trees automatically. Need I say more ;-)
+trees automatically. Need you say more ;-)
=item It's a good reference
excellent point to start with when choosing to use the 'rsync the
patches' scheme. Starting with perl@7582, which means a set of source
files on which the latest applied patch is number 7582, you apply all
-succeeding patches available from than on (7583, 7584, ...).
+succeeding patches available from then on (7583, 7584, ...).
You can use the patches later as a kind of search archive.
If you want to fix/change the behaviour of function/feature Foo, just
scan the patches for patches that mention Foo either in the subject,
-the comments, or the body of the fix. A good change the patch shows
+the comments, or the body of the fix. A good chance the patch shows
you the files that are affected by that patch which are very likely
to be the starting point of your journey into the guts of perl.
=item Finding the source of misbehaviour
When you keep in sync with bleadperl, the pumpking would love to
-I<see> that the community efforts realy work. So after each of his
+I<see> that the community efforts really work. So after each of his
sync points, you are to 'make test' to check if everything is still
in working order. If it is, you do 'make ok', which will send an OK
report to perlbug@perl.org. (If you do not have access to a mailer
-from the sytem you just finished successfully 'make test', you can
+from the system you just finished successfully 'make test', you can
do 'make okfile', which creates the file C<perl.ok>, which you can
than take to your favourite mailer and mail yourself).
-But of course, as allways, things will not allways lead to a success
+But of course, as always, things will not always lead to a success
path, and one or more test do not pass the 'make test'. Before
sending in a bug report (using 'make nok' or 'make nokfile'), check
the mailing list if someone else has reported the bug already and if
trace the source of that misbehaviour B<before> sending in the bug,
which will help all the other porters in finding the solution.
-Here the saved patches come in very handy. You can check in there
-which patch changed what file and what change caused the
-misbehaviour. If you note that in the bug report, it saves the one
-trying to solve it, looking for that point.
+Here the saved patches come in very handy. You can check the list of
+patches to see which patch changed what file and what change caused
+the misbehaviour. If you note that in the bug report, it saves the
+one trying to solve it, looking for that point.
=back
=back
+If you want to get the best of both worlds, rsync both the source
+tree for convenience, reliability and ease and rsync the patches
+for reference.
+
=head2 Submitting patches
Always submit patches to I<perl5-porters@perl.org>. This lets other
To report a bug in Perl, use the program I<perlbug> which comes with
Perl (if you can't get Perl to work, send mail to the address
-I<perlbug@perl.com> or I<perlbug@perl.org>). Reporting bugs through
+I<perlbug@perl.org> or I<perlbug@perl.com>). Reporting bugs through
I<perlbug> feeds into the automated bug-tracking system, access to
which is provided through the web at I<http://bugs.perl.org/>. It
often pays to check the archives of the perl5-porters mailing list to
7 call_method("PUSH", G_SCALAR|G_DISCARD);
8 LEAVE;
9 POPSTACK;
-
+
The lines which concern the mark stack are the first, fifth and last
lines: they save away, restore and remove the current position of the
argument stack.
1 PP(pp_add)
2 {
- 3 djSP; dATARGET; tryAMAGICbin(add,opASSIGN);
+ 3 dSP; dATARGET; tryAMAGICbin(add,opASSIGN);
4 {
5 dPOPTOPnnrl_ul;
6 SETn( left + right );
Some of the functionality of the debugging code can be achieved using XS
modules.
-
+
-Dr => use re 'debug'
-Dx => use O 'Debug'
=item break source.c:xxx
Tells the debugger that we'll want to pause execution when we reach
-either the named function (but see L</Function names>!) or the given
+either the named function (but see L<perlguts/Internal Functions>!) or the given
line in the named source file.
=item step
Run until the end of the current function, then stop again.
-=item
+=item 'enter'
Just pressing Enter will do the most recent operation again - it's a
blessing when stepping through miles of source code.
(gdb) break Perl_pp_add
Breakpoint 1 at 0x46249f: file pp_hot.c, line 309.
-Notice we use C<Perl_pp_add> and not C<pp_add> - see L<perlguts/Function Names>.
+Notice we use C<Perl_pp_add> and not C<pp_add> - see L<perlguts/Internal Functions>.
With the breakpoint in place, we can run our program:
(gdb) run -e '$b = "6XXXX"; $c = 2.3; $a = $b + $c'
libraries, and then:
Breakpoint 1, Perl_pp_add () at pp_hot.c:309
- 309 djSP; dATARGET; tryAMAGICbin(add,opASSIGN);
+ 309 dSP; dATARGET; tryAMAGICbin(add,opASSIGN);
(gdb) step
311 dPOPTOPnnrl_ul;
(gdb)
All done. Now let's create the patch. F<Porting/patching.pod> tells us
that if we're making major changes, we should copy the entire directory
to somewhere safe before we begin fiddling, and then do
-
+
diff -ruN old new > patch
However, we know which files we've changed, and we can simply do this:
which would instrument Perl in memory, run Perl on test.pl,
then finally report any memory problems.
+=head2 Compaq's/Digital's Third Degree
+
+Third Degree is a tool for memory leak detection and memory access checks.
+It is one of the many tools in the ATOM toolkit. The toolkit is only
+available on Tru64 (formerly known as Digital UNIX formerly known as
+DEC OSF/1).
+
+When building Perl, you must first run Configure with -Doptimize=-g
+and -Uusemymalloc flags, after that you can use the make targets
+"perl.third" and "test.third".
+
+The short story is that with "atom" you can instrument the Perl
+executable to create a new executable called F<perl.third>. When the
+instrumented executable is run, it creates a log of dubious memory
+traffic in file called F<perl.3log>. See the manual pages of atom and
+third for more information. The most extensive Third Degree
+documentation is available in the Compaq "Tru64 UNIX Programmer's
+Guide", chapter "Debugging Programs with Third Degree".
+
+The "test.third" leaves a lot of files named F<perl.3log.*> in the t/
+subdirectory. There is a problem with these files: Third Degree is so
+effective that it finds problems also in the system libraries.
+Therefore there are certain types of errors that you should ignore in
+your debugging. Errors with stack traces matching
+
+ __actual_atof|__catgets|_doprnt|__exc_|__exec|_findio|__localtime|setlocale|__sia_|__strxfrm
+
+(all in libc.so) are known to be non-serious. You can also
+ignore the combinations
+
+ Perl_gv_fetchfile() calling strcpy()
+ S_doopen_pmc() calling strcmp()
+
+causing "rih" (reading invalid heap) errors.
+
+There are also leaks that for given certain definition of a leak,
+aren't. See L</PERL_DESTRUCT_LEVEL> for more information.
+
+=head2 PERL_DESTRUCT_LEVEL
+
+If you want to run any of the tests yourself manually using the
+pureperl or perl.third executables, please note that by default
+perl B<does not> explicitly cleanup all the memory it has allocated
+(such as global memory arenas) but instead lets the exit() of
+the whole program "take care" of such allocations, also known
+as "global destruction of objects".
+
+There is a way to tell perl to do complete cleanup: set the
+environment variable PERL_DESTRUCT_LEVEL to a non-zero value.
+The t/TEST wrapper does set this to 2, and this is what you
+need to do too, if you don't want to see the "global leaks":
+
+ PERL_DESTRUCT_LEVEL=2 ./perl.third t/foo/bar.t
+
+=head2 Gprof Profiling
+
+gprof is a profiling tool available in many UNIX platforms.
+The profiling is based on statistical time-sampling; this means that
+some routines, especially those executing really fast, may be missed.
+
+You can build a profiled version of perl called "perl.gprof" by
+invoking the make target "perl.gprof". Running the profiled version
+of Perl will create an output file called F<gmon.out> is created which
+contains the profiling data collected during the execution.
+
+The gprof tool can then display the collected data in various ways.
+Usually gprof understands the following options:
+
+=over 4
+
+=item -a
+
+Suppress statically defined functions from the profile.
+
+=item -b
+
+Suppress the verbose descriptions in the profile.
+
+=item -e routine
+
+Exclude the given routine and its descendants from the profile.
+
+=item -f routine
+
+Display only the given routine and its descendants in the profile.
+
+=item -s
+
+Generate a summary file called F<gmon.sum> which then may be given
+to subsequent gprof runs to accumulate data over several runs.
+
+=item -z
+
+Display routines that have zero usage.
+
+=back
+
+For more detailed explanation of the available commands and output
+formats, see your own local documentation of gprof.
+
+=head2 Pixie Profiling
+
+Pixie is a profiling tool available on IRIX and Tru64
+(aka Digital UNIX aka DEC OSF/1) platforms. Pixie does its profiling
+using "basic-block counting". A basic block is a program region that
+is entered only at the beginning and exited only at the end.
+
+You can build a profiled version of perl called F<perl.pixie> by
+invoking the make target "perl.pixie" (in Tru64 a file called
+F<perl.Addrs> will also be silently created, this file contains the
+addresses of the basic blocks). Running the profiled version of Perl
+will create a new file called "perl.Counts" which contains the counts
+for the basic block for that particular program execution.
+
+To display the results you must use the "prof" utility. The exact
+incantation depends on your operating system, "prof perl.Counts" in
+IRIX, and "prof -pixie -all -L. perl" in Tru64.
+
+In IRIX the following prof options are available:
+
+=over 4
+
+=item -h
+
+Reports the most heavily used lines in descending order of use.
+Useful for finding the hotspot lines.
+
+=item -l
+
+Groups lines by procedure, with procedures sorted in descending order of use.
+Within a procedure, lines are listed in source order.
+Useful for finding the hotspots of procedures.
+
+=back
+
+In Tru64 the following options are available:
+
+=over 4
+
+=item -p[rocedures]
+
+Procedures sorted in descending order by the number of cycles executed
+in each procedure. Useful for finding the hotspot procedures.
+(This is the default option.)
+
+=item -h[eavy]
+
+Lines sorted in descending order by the number of cycles executed in
+each line. Useful for finding the hotspot lines.
+
+=item -i[nvocations]
+
+The called procedures are sorted in descending order by number of calls
+made to the procedures. Useful for finding the most used procedures.
+
+=item -l[ines]
+
+Grouped by procedure, sorted by cycles executed per procedure.
+Useful for finding the hotspots of procedures.
+
+=item -testcoverage
+
+The compiler emitted code for these lines, but the code was unexecuted.
+
+=item -z[ero]
+
+Unexecuted procedures.
+
+=back
+
+For further information, see your system's manual pages for pixie and prof.
+
=head2 CONCLUSION
We've had a brief look around the Perl source, an overview of the stages
=item *
-Do read the README associated with your operating system, i.e. README.aix
+Do read the README associated with your operating system, e.g. README.aix
on the IBM AIX OS. Don't hesitate to supply patches to that README if
you find anything missing or changed over a new OS release.
https://perl5.git.perl.org / perl5.git / blobdiff