El Dilluns, 30 de gener de 2012, a les 00:03:13, Albert Astals Cid va escriure: > El Diumenge, 29 de gener de 2012, a les 17:27:43, Maria, Marti va escriure: > > Great, I would suggest just one test more. Try to convert a PDF with an > > huge raster image > 400Mb. The xput gain of lcms2 should be evident in > > this case. Regards. > > I am not denying there will not be an improvement in this case.
I think i have one too man "not" in there but i hope my message was understood. Albert > It is just > that i prefer it to be "as fast" as it was before, not faster in some cases > and slower in others. > > Albert > > > Marti > > > > -----Original Message----- > > From: Albert Astals Cid [mailto:tsdg...@gmail.com] On Behalf Of Albert > > Astals Cid Sent: sábado, 28 de enero de 2012 16:48 > > To: poppler@lists.freedesktop.org > > Cc: Maria, Marti; seb...@ubuntu.com; Till Kamppeter; Koji Otani > > Subject: Re: [poppler] Migrating poppler to liblcms2 from liblcms1 > > > > El Divendres, 27 de gener de 2012, a les 18:23:50, Albert Astals Cid va > > > > escriure: > > > El Divendres, 27 de gener de 2012, a les 10:39:18, Maria, Marti va > > escriure: > > > > Bon dia Albert, > > > > > > Hola > > > > > > > That makes a lot of sense. Lcms2 spends more time on optimizing > > > > the > > > > transform in order to make it faster. That means create > > > > transform is > > > > currently slower that lcms1 but applying transforms is way > > > > faster. > > > > This was indeed a design decision, as most of time creation of > > > > transforms happens only once at the very beginning and then this > > > > transform is applied to huge amounts of raster. The performance > > > > tests I send didn't take creation time into account. > > > > > > > > I will take this action item to review creation time in the next > > > > release. > > > > Otherwise, you may consider reusing transforms. > > > > > > We reuse the transforms, it is just that this file has lots of them. > > > > > > > That would speed up both > > > > lcms1 and lcms2. If this is not feasible, there is a flags > > > > cmsFLAGS_NOOPTIMIZE, that makes transform creation fast, at the > > > > expense of slower dotransfom operation. This is not recommended > > > > at > > > > all because you disable all optimizations, but may solve the > > > > issue > > > > when creating transforms that are applied only to few bytes. > > > > > > Not sure if i can now to how many bytes it'll be applied but i'll do > > > some testing and maybe just enable it for the time being so at least > > > we have the same behaviour than when using lcms1, might not be > > > faster > > > but we not slower either. > > > > Using cmsFLAGS_NOOPTIMIZE brings back altona_technical_1v2_x3.pdf to an > > acceptable speed again. > > > > Koji can you please update your patch so it uses the cmsFLAGS_NOOPTIMIZE > > when compiling with lmcs2? > > > > Albert > > > > > Thanks, > > > > > > Albert > > > > > > > Again, thanks for reporting. I'm putting the transform creation > > > > time > > > > issue high in my priority list. > > > > > > > > Best regards > > > > > > > > Marti Maria, Color Engineer > > > > HP Large Format Printers Division - Barcelona marti.ma...@hp.com > > > > > > > > > > > > > > > > -----Original Message----- > > > > From: Albert Astals Cid [mailto:tsdg...@gmail.com] On Behalf Of > > > > Albert Astals Cid Sent: jueves, 26 de enero de 2012 19:43 > > > > To: poppler@lists.freedesktop.org > > > > Cc: Maria, Marti; Till Kamppeter; seb...@ubuntu.com > > > > Subject: Re: [poppler] Migrating poppler to liblcms2 from > > > > liblcms1 > > > > > > > > El Dilluns, 23 de gener de 2012, a les 11:16:03, Maria, Marti va > > escriure: > > > > > Hi, > > > > > In my testings lcms2 is significantly faster that lcms1 > > > > > except > > > > > when using floating point, then lcms2 favors precision. > > > > > > > > Is this precision is so important to justify a 10x slowliness? > > > > Maybe > > > > it'd be a good idea to have a fallback fast mode for those not > > > > willing to take that 10x hit? > > > > > > > > > http://littlecms2.blogspot.com/2010/03/xput-comparative-119- > > > > > vs-2 > > > > > 0. > > > > > ht > > > > > ml > > > > > > > > > > Altona test does many different color conversions it would > > > > > be > > > > > interesting to know which transformation is going slow. > > > > > > > > Attached the callgrind output of running poppler there, you can > > > > see > > > > the time is almost totally spent on creating the transforms. > > > > > > > > Wild guess: I'm wondering if the thing is that not > > > > transformations > > > > are all precalculated (meaning a faster overall if you do lots > > > > of > > > > access) and previously they were done each time and thus if we > > > > end > > > > up doing "few" transformations it was just much faster? > > > > > > > > Cheers, > > > > > > > > Albert > > > > > > > > > Regards > > > > > Marti > > > > > > > > > > ________________________________________ > > > > > From: Till Kamppeter [till.kamppe...@gmail.com] > > > > > Sent: Monday, January 23, 2012 8:58 AM > > > > > To: Albert Astals Cid > > > > > Cc: poppler@lists.freedesktop.org; Maria, Marti; Sebastien > > > > > Bacher; > > > > > Koji Otani Subject: Re: [poppler] Migrating poppler to > > > > > liblcms2 > > > > > from > > > > > > > > > > liblcms1 On 01/22/2012 11:18 PM, Albert Astals Cid wrote: > > > > > > Same thing, altona_technical_1v2_x3.pdf still goes up > > > > > > from x > > > > > > seconds to 10x seconds when going from lcms1 to lcms2. > > > > > > > > > > > > That is in my opinion not acceptable (of course i'm not > > > > > > ruling > > > > > > out that we in poppler are using lcms2 wrong). Till, > > > > > > does > > > > > > your > > > > > > ubuntu work cover fixing the regressions of moving from > > > > > > lcms1 to > > > > > > lcms2 or all your work covers is making stuff compile? > > > > > > > > > > I downloaded altona_technical_1v2_x3.pdf from > > > > > http://www.eci.org/doku.php?id=es:downloads and tried > > > > > pdftops on > > > > > Ubuntu Oneiric (11.10, lcms1) and on Precise (12.04, lcms2, > > > > > Koji > > > > > Otani's patch) and with lcms1 it takes 3.5 seconds and with > > > > > lcms2 > > > > > 17.5 > > > > > seconds. > > > > > > > > > > The same problem occurs with Ghostscript: There the same > > > > > transition happened from Oneiric to Precise and here Oneiric > > > > > is > > > > > much faster with this file, too. In Precise PDF rendering > > > > > for > > > > > printing is done by Ghostscript and not by Poppler, so lcms2 > > > > > is > > > > > already used for printing in Precise for some time. As there > > > > > are > > > > > no performance complaints by users yet, it seems that for > > > > > everyday > > > > > files there is not such a significant performance loss. and > > > > > this > > > > > > > > > > Marti, can you check what is the problem with lcms2 and this > > > > > PDF > > > > > file and also why most files are somewhat slower with lcms2? > > > > > > > > > > Till > > > > > > > > > > _______________________________________________ > > > > > poppler mailing list > > > > > poppler@lists.freedesktop.org > > > > > http://lists.freedesktop.org/mailman/listinfo/poppler > > > > > > _______________________________________________ > > > poppler mailing list > > > poppler@lists.freedesktop.org > > > http://lists.freedesktop.org/mailman/listinfo/poppler > > _______________________________________________ > poppler mailing list > poppler@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/poppler _______________________________________________ poppler mailing list poppler@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/poppler
