[tlbuild] TL installation on Cygwin is slow

[Ken Brown]

On 11/12/2014 6:34 PM, Reinhard Kotucha wrote:
> Hi Ken,
> from previous messages on this list I conclude that you are
> maintaining TL on Cygwin.
>
> I recently installed Cygwin and it took a lot of time to install the
> TeX Live packages.  Though I installed zillions of other packages too,
> the installer spent most of the time executing the TeX Live
> postinstall scripts.  The reason is that there are way too many
> invocations of mktexlsr, many of them are unnecessary.
>
> Example:
>
> texlive-collection-langgreek.sh
> -------------------------------------------------------------------------
> /usr/bin/mktexlsr
> /usr/bin/updmap-sys --nohash --nomkmap --enable MixedMap=cbgreek-full.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable Map=gfsbaskerville.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable Map=gfsporson.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable MixedMap=iby.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable Map=kerkis.map
> /usr/bin/updmap-sys --nohash --syncwithtrees
> /usr/bin/updmap-sys --nohash
> /usr/bin/mktexlsr
> /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/opentype
> /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/type1
> -------------------------------------------------------------------------
>
> The first invocation of mktexlsr is unavoidable (at a first glance)
> because new files had been installed and updmap-sys has to find them.
> However, both, mktexlsr and updmap-sys can be run later, see below.
>
> As a first measure I suggest to simply replace
>
>    /usr/bin/updmap-sys --nohash
>    /usr/bin/mktexlsr
>
> with
>
>    /usr/bin/updmap-sys
>
> This speeds up everything significantly.
>
> Without the --nohash option updmap-sys appends an entry to
> $TEXMFSYSVAR/ls-R for every file it has written.  No need to run
> mktexlsr at all.  This is very efficient because there is no need to
> scan the filesystem.
>
> mktexlsr is a very expensive operation, especially if $TEXMFDIST is
> involved, and should be avoided whenever possible.
>
> Another expensive operation is updmap-sys --syncwithtrees.  It's less
> expensive than mktexlsr because it only checks whether files mentioned
> in updmap.cfg are present on the filesystem.  It's only needed if .map
> files had been removed from the filesystem.  Maybe it's sufficient to
> run updmap-sys --nohash --syncwithtrees only if updmap-sys fails.
>
>    updmap-sys || (echo y|updmap-sys --nohash --syncwithtrees;updmap-sys)
>
> I'm not sure (I was at lunch while the installer was running) but it
> seems that all the postinstall scripts are executed after all files
> had been installed.  In this case it's possible to run the
> time-consuming scripts only once.  The scripts should then contain
> the --enable commands only:
>
> texlive-collection-langgreek.sh
> -------------------------------------------------------------------------
> /usr/bin/updmap-sys --nohash --nomkmap --enable MixedMap=cbgreek-full.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable Map=gfsbaskerville.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable Map=gfsporson.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable MixedMap=iby.map
> /usr/bin/updmap-sys --nohash --nomkmap --enable Map=kerkis.map
> -------------------------------------------------------------------------
>
> Please note that at this point it's not necessary to run mktexlsr
> because only the value of --enable is added to updmap.cfg.  These
> operations are very cheap and time consumption is negligible.
>
> Then texlive.sh should look like this:
>
> -------------------------------------------------------------------------
> /usr/bin/mktexlsr
> /usr/bin/fmtutil-sys --refresh
> /usr/bin/updmap-sys --nohash --syncwithtrees
> /usr/bin/updmap-sys
> /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/opentype
> /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/type1
> /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/truetype
> -------------------------------------------------------------------------
>
> In this case all the expensive scripts become inexpensive because they
> are run only once.  In order to take into account that some
> collections don't contain any fonts you can suppress updmap and
> fc-cache.  The postinstall scripts for collections containing fonts
> should contain the line
>
>    touch /var/run/process-texlive-fonts
>
> And texlive.sh could look like this:
>
> -------------------------------------------------------------------------
> /usr/bin/mktexlsr
> /usr/bin/fmtutil-sys --refresh
> if [ -f /var/run/process-texlive-fonts ]; then
>    /usr/bin/updmap-sys --nohash --syncwithtrees
>    /usr/bin/updmap-sys
>    /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/opentype
>    /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/type1
>    /usr/bin/fc-cache -f /usr/share/texmf-dist/fonts/truetype
> fi
> rm -f /var/run/process-texlive-fonts
> -------------------------------------------------------------------------
>
> After all, I think that some kind of optimization is very helpful.
> Though Cygwin is a Unix environment, it runs under Windows and thus is
> extremely slow.  I don't know what makes Windows so slow but I suppose
> that the filesystem is the main culprit.  Maybe creating new processes
> is expensive too.
>
> Currently the installer runs mktexlsr at least once for every package
> end even twice if a particular package contains fonts.  My impression
> is that the current installer unnecessarily wastes more than one hour
> in order to do unnecessary things at each full TL installation.  I'm
> convinced that it's not difficult to improve it significantly without
> great effort.

Hi Reinhard,

Thanks very much for the suggestions.  I'll see what I can do.

Ken