User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040124 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040124 Opening a 5MB of very simple XML document (max. depth 3, only a few types of elements) in Mozilla window consumes over 500MB. Even after the whole document has been parsed, Mozilla response time is terribly slow. My system is Athlon 2400+, 512MB RAM, so it's not some slow junk. By comparasion MSIE parses same document not only faster, but also consuming only 60MB of memory. Reproducible: Always Steps to Reproduce: 1. Open a large XML document 2. 3. Actual Results: Document opens very slow, Mozilla-bin eats up memory, and is extremely slow to respond to user commands (eg. switching to different tab or window). Expected Results: Performance at least comparable with MSIE I do not attach XML file, becouse it contains sensitive data. Should you need it, I could generate one with fake data.

If your file uses XSLT stylesheet it is a known issue (see bug 197956). (Note that if it has no stylesheet in itself, Mozilla assigns it a default XSLT stylesheet which provides the IE-like tree view.)

(In reply to comment #1) > If your file uses XSLT stylesheet it is a known issue (see bug 197956). (Note > that if it has no stylesheet in itself, Mozilla assigns it a default XSLT > stylesheet which provides the IE-like tree view.) Is there any chance that this will be fixed in forseable future? Are you planing to switch from Expat to more effective libXML2 and libXSLT anytime soon? How about workaround, is it possible to display XML without XSL[T] as plain text?

(In reply to comment #2) > Is there any chance that this will be fixed in forseable future? Are you planing > to switch from Expat to more effective libXML2 and libXSLT anytime soon? No plans as far as I know. It would need a volunteer to do that. I heard Jonas Sicking was working on integrating a validating parser into Mozilla, but it may have been a hack - dunno. The last time we looked at integrating libxml or libxslt it looked like it would have been extremely difficult to do (2-3 years ago), because of difference in how Expat and libxml were intended to be integrated into products. > How about workaround, is it possible to display XML without XSL[T] as plain text? Yeah, serve it as text/plain mime type. Easiest thing to do would be to change the file suffix to .txt, for example. Mozilla would also handle your XML fast if you provided a CSS stylesheet for it.

*** Bug 266895 has been marked as a duplicate of this bug. ***

Marking as new based on other dupe. Does anyone know if XLST has anything to do with either instance of this bug?

Bug 266895 does not have a stylesheet, so we assign the default XSLT transformation to it, and since that is slow it is bug 197956. There is no testcase here, but based on comments I believe this is the same issue, so again bug 197956. Btw, another workaround would be to prepend view-source: to the URL - that way it won't go through XML processing. *** This bug has been marked as a duplicate of 197956 ***

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