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posted 5 years ago
20tsed56 1 post

Forum: Instiki – Topic: Debugging uninterruptible sleep

that is huge data to handle …

 
posted 5 years ago
Andrew Stacey 118 posts

Forum: Instiki – Topic: Debugging uninterruptible sleep

Agree completely.

The processes that were handling the list call were entering uninterruptible sleep and were using a large amount of memory - of the order of 300Mb to 500Mb. The system would get bogged down if there were more than one of them, but even one would take a reasonable amount of time to complete.

My suspicion is therefore that it relates to writing the file to disk for caching. So I suspect that there really is a problem with the hardware and that having several processes trying to write the same file was exposing it.

(There was a change in hardware underpinning the VPS recently.)

 
posted 5 years ago
distler 108 posts

Forum: Instiki – Topic: Debugging uninterruptible sleep

It looks as though it is the “All Pages” request that is clogging up the works, … at 7000 pages then it’s a bit cumbersome, to say the least,

I have no idea why that would be an issue.

It’s not as if Instiki has to do anything with those 7000 pages, apart from retrieving an alphabetical list of their names (and URLs). If that’s indeed your problem, it would be nice to know why.

 
posted 5 years ago
Andrew Stacey 118 posts

Forum: Instiki – Topic: Debugging uninterruptible sleep

I’ve added the timestamps and process ids to the logs and that’s made things a lot clearer. It looks as though it is the “All Pages” request that is clogging up the works, and there appear to be some spiders that don’t respect robots.txt and find “All Pages” fairly early on in their crawl.

You’ve mentioned before the possibility of adding a pageinate routine to “All Pages”. Would that help me, do you think? Or is it easier just to disable it (at 7000 pages then it’s a bit cumbersome, to say the least, so I’ve no compunction at simply disabling it altogether).

Incidentally, I found I’d forgotten that bzr doesn’t set permissions so some stuff in public was unreadable. That might explain why the SVG editor wasn’t working for me as there were a couple of files from that affected.

 
posted 5 years ago
Andrew Stacey 118 posts

Forum: Instiki – Topic: Debugging uninterruptible sleep

I strongly doubt that it is due to instiki itself, but it would be nice to isolate exactly what causes the problem. Thanks for the link.

After watching top all day, I think things are going into D state far more than I would expect so I’m going to contact our server provider.

To help in debugging this, I’m going to add the process pid to the logging messages as that’ll make it easier to link what I see in top to what I see in the production.log.

 
posted 5 years ago
admin 58 posts

edited 5 years ago

Forum: Instiki – Topic: Debugging uninterruptible sleep

Attach gdb to the process and try to figure out where it’s stuck. It would be interesting to me if there was an Instiki-specific reason these processes were getting stuck.

But, so far, there’s no evidence for that.

 
posted 5 years ago
Andrew Stacey 118 posts

Forum: Instiki – Topic: Debugging uninterruptible sleep

I’m getting a slew of processes getting into “uninterruptible sleep” and staying there. They sit there, eating CPU and memory, until the system slows down enough that folks complain.

Do you happen to know how to debug these? From what I’ve read, this is likely to be something getting stuck on I/O.

One thing that occurred to me was that all the processes are logging to the same file. Could they get stuck in some sort of queue for that?

(Also from my reading around, it would appear that the root cause of this is more likely to be at the kernel end, and thus an issue with drivers and hardware, than with instiki. Still, I’d like to know what it is that is triggering the sleep.)

 
posted 5 years ago
distler 108 posts

Forum: Heterotic Beast – Topic: MathJax 2.0

The latest commits, to Heterotic Beast, upgrade it to MathJax 2.0 (from 1.1). This loads (a little) faster, and also sports a SVG rendering option (selectable from the context menu).

 
posted 5 years ago
distler 108 posts

Forum: Instiki – Topic: MathJax 2.0

The latest commits, to Instiki, upgrade it to MathJax 2.0 (from 1.1). This loads (a little) faster, and also sports a SVG rendering option (selectable from the context menu).

 
posted 5 years ago
admin 58 posts

Forum: Instiki – Topic: S5 vertical alignment

I don’t know of a totally robust way to do it. My CSS-fu is weak.

But

Test Vertical Alignment
------------------------

This is centered on the slide
{: style="margin-top:25%;text-align:center;}

is a pretty good approximation to what you want.

 
posted 5 years ago
admin 58 posts

edited 5 years ago

Forum: Instiki – Topic: Bugs

And another one, this time in how maruku parses its meta-data.

This was actually only a problem for IALs attached to <li> elements. Fixed in the latest Maruku.

(This commit gives the complete solution. Its predecessor was only a partial fix.)

(N.b.: Maruku is now unvendored, so a

ruby bundle update

will pull in the latest version from Github.)

I’m unable to run the inbuilt SVG editor on my computer (running Mac OS X, Lion).

Works fine for me under Lion. (I haven’t updated to Mountain Lion, so I can’t make any promises about that. But I’d be surprised if there were any OS dependence of this; it ought to be a function of the Javascript engine in your browser. Or perhaps I misunderstood: were you running the server on Lion, or just the client?)

 
posted 5 years ago
Andrew Stacey 118 posts

Forum: Instiki – Topic: Bugs

And another one, this time in how maruku parses its meta-data. It would seem that not leaving a space at the end of {: #identifier} means that the } gets into the identifier.

Presumably this is the case here as well:

  • What’s the id of this element?

I get:

<ul>
<li id='list}'>What’s the <code>id</code> of this element?</li>
</ul>

in the source.

 
posted 5 years ago
Andrew Stacey 118 posts

Forum: Instiki – Topic: Bugs

I’m unable to run the inbuilt SVG editor on my computer (running Mac OS X, Lion). The window launches but none of the icons are present and although the buttons highlight when I hover over them, nothing happens when I click on one.

This is with Firefox, Chrome, and Safari. Not sure what additional information you would like on this.

 
posted 5 years ago
cameron smith 1 post

Forum: Instiki – Topic: S5 vertical alignment

I apologize if I missed it somewhere else, but how do you specify that the content on each slide in an S5 slide show should be vertically centered?

 
posted 5 years ago
jl345 6 posts

Forum: Instiki – Topic: Bugs

I tried a little test case…

$ cat subtest.rb                                                                                                                                                               
#!/usr/bin/env ruby
puts '/some/other/string'.gsub( '/some/other' + File::SEPARATOR, '' )
puts '/some/other/string'.gsub( Regexp.escape( '/some/other' + File::SEPARATOR), '' )
puts '/some/other/string'.gsub( Regexp.new( Regexp.escape( '/some/other' + File::SEPARATOR ) ), '' )
$ ./subtest.rb                                                                                                                                                                 
string
string
string
$ ruby --version
ruby 1.8.7 (2012-06-29 patchlevel 370) [x86_64-openbsd]

I believe that my first and third examples are both correct and equivalent, going by official docs. The second example works, too, in this case, because a forward slash is apparently not one of the characters escaped by Regexp.escape(), which is curious, because now I am unable to reproduce the error that occurred in the rake task before I altered the code. So I’m more and more confused.

 
posted 5 years ago
distler 108 posts

Forum: Instiki – Topic: Bugs

Hmmm. Both look wrong. What I think we want is:

table_name = f.gsub( Regexp.new(Regexp.escape(Rails.root.join('dump','fixtures').to_s + File::SEPARATOR)), '').gsub('.yml', '')

The point being that the output of Regexp.escape is a (properly-escaped) string which is suitable as input to Regexp.new.

 
posted 5 years ago
jl345 6 posts

edited 5 years ago

Forum: Instiki – Topic: Bugs

--- instiki-0.19.4/lib/tasks/fixtures.rake.orig Sat Jun 30 19:40:02 2012
+++ instiki-0.19.4/lib/tasks/fixtures.rake      Wed Jul 18 01:33:06 2012
@@ -74,7 +74,7 @@
     task :import_all => :environment do
       ActiveRecord::Base.establish_connection
       Dir.glob(Rails.root.join('dump','fixtures',"*.yml")).each do |f|
-        table_name = f.gsub( Regexp.escape(Rails.root.join('dump','fixtures').to_s + File::SEPARATOR), '').gsub('.yml', '')
+        table_name = f.gsub( Rails.root.join('dump','fixtures').to_s + File::Separator, '').gsub('.yml', '')
          puts "Importing #{table_name}"
         import_table_fixture(table_name)
       end

That’s what I have anyways, but be careful, because somehow I got File::SEPARATOR in the wrong case in my bumbling around. I guess I got lucky: File::Separator is defined too, so no harm done.

 
posted 5 years ago
distler 108 posts

Forum: Instiki – Topic: Bugs

If you’ve found a mistake in the rake task, please send me a patch.

 
posted 5 years ago
jl345 6 posts

Forum: Instiki – Topic: Bugs

Ahh!

I figured out what went wrong with my PostgresQL import. The tables were just fine in fact; just the last sequence numbers for all the primary keys had all gotten set to one for some reason. It worked fine once I got the sequence numbers adjusted to the last row in each table, so now my installation of Instiki appears to be working great on PostgreSQL.

Again, Instiki is an awesome wiki, and I’m already using it to take math notes and such for stuff I have to learn.

 
posted 5 years ago
jl345 6 posts

Forum: Instiki – Topic: Bugs

Hi!

I was experimenting around, trying to migrate this wiki to PostgreSQL 9.1.4, following your instructions, and I think there was a little bug in instiki-0.19.4/lib/tasks/fixtures.rake, line 77, where it looks like a string was escaped for a regular expression, but then it was being matched as a literal string with all the extra backslashes. After I think I more or less fixed this, I was able to run

$ env RAILS_ENV=production bundle exec rake db:migrate --trace

$ env RAILS_ENV=production bundle exec rake db:fixtures:import_all --trace

Now my database has all the tables in it, populated with rows, and I can view the pages, but when I try to edit a page, there is an error, because it looks like the primary keys were not set up properly on these tables, so I’m still trying to figure this out. Any ideas? (I think I need to make sure there is utf8 support, too…)

Thanks!

 
posted 5 years ago
jl345 6 posts

edited 5 years ago

Forum: itex2MML – Topic: weird math fonts

I didn’t mean to do that, but you like to make the forum better and better, so all’s well that ends well, I hope…

With the STIX fonts, those letters do all look the same, in the curlier script. *** However, I think part of the problem is that the calligraphic BEFHIKLM live in a totally different area of Unicode than the other calligraphic letters. Your ”ℬ” at U+212C certainly doesn’t immediately follow the ”𝒜” at U+1D49C. The very next symbol after ”𝒜” is ”𝒝” (undefined), followed by ”𝒞” and ”𝒟”, because the Unicrats who designed these things in their infinite wisdom ensured that only a portion of the “calligraphic” alphabet was put in a different codepage on an alternate plane of existence, where some fonts may or may not even have glyphs, and the glyph may very well look different, because there is absolutely no assurance in Unicode of any consistency in the way fonts are going to be applied across such vastly different planes of the code space. Why isn’t it possible to put real ASCII letters in a calligraphic font? Seems like it should work but it doesn’t, in my browser anyways:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0 plus SVG 1.1//EN"
"http://www.w3.org/2002/04/xhtml-math-svg/xhtml-math-svg.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><title>Probability Space</title></head>
<body>
<math xmlns="http://www.w3.org/1998/Math/MathML">
  <mfenced>
    <mi>Ω</mi>
    <mi mathvariant='script'>F</mi>
    <mi mathvariant='double-struck'>P</mi>
  </mfenced>
</math>
</body>
</html>`
 
posted 5 years ago
distler 108 posts

Forum: Heterotic Beast – Topic: MySQL Gotcha

If you’re going to use Heterotic Beast in production, you need to be running MySQL 5.5.3 or later, and follow the advice in this blog post.

Otherwise, the lack of support for Unicode will come back to bite you.

 
posted 5 years ago
distler 108 posts

Forum: itex2MML – Topic: weird math fonts

P.S.: Congratulations on figuring out how to make this page ill-formed! It took a bit of work to fix the issue.

 
posted 5 years ago
admin 58 posts

edited 5 years ago

Forum: itex2MML – Topic: weird math fonts

Perhaps you need to install the STIX fonts (see here for some slightly out-of-date, but still useful instructions).

I see those calligraphic letters all set in the same font. And, moreover and are set upright (as, for that matter, are 𝔸 and 𝕓).

Alas, what you see is strongly-dependent on what fonts you have installed.

In more detail:

On my system, ℬ (U+212C) is available in STIXGeneral, Apple Symbols and Arial Unicode MS. But 𝒜 (U+1D49C) is only available in STIXGeneral. In current versions of Firefox, I believe the default value of font.mathfont-family is

MathJax_Main, STIXNonUnicode, STIXSizeOneSym, STIXSize1, STIXGeneral, Asana Math, Symbol,
   DejaVu Sans, Cambria Math

so the version in STIXGeneral is what I see.

 
posted 5 years ago
jl345 6 posts

edited 5 years ago

Forum: itex2MML – Topic: weird math fonts

Maybe it’s just general persnicketiness on my part, but why do ℬℰℱℋℐℒℳℛ appear (in Firefox and rekonq) in a different type than the letters 𝒜𝒞𝒟𝒢𝒥𝒦𝒩𝒪𝒫𝒬𝒮𝒯𝒰𝒱𝒲𝒳𝒴𝒵? And how can I get a letter like or to stand upright like ℙℚ but by itself without getting italicized?

(Sorry for the new username. I lost my password and for some reason Yahoo can’t get mail from the forums.)

 
posted 5 years ago
jl344 4 posts

Forum: itex2MML – Topic: Bugs

Good enough then and thank you. I thought $X_a b$ was producing an unacceptable space, but that was just a Firefox peculiarity.

 
posted 5 years ago
admin 58 posts

Forum: itex2MML – Topic: Bugs

That’s a “feature”, not a bug.

As described here, $ab$ is a single token in itex (tranlated to <mi>ab</mi>); $a b$ are two tokens (translated to <mi>a</mi><mi>b</mi>). MathML is semantically-richer than (La)TeX, and this convention gives you the ability to enter multi-character tokens, which will be interpreted as such, when translated to MathML.

 
posted 5 years ago
jl344 4 posts

Forum: itex2MML – Topic: Bugs

Identifiers lumped together in MathML output

Example: $X_ab$ produces output X ab <msub><mi>X</mi> <mi>ab</mi></msub>

Output should be more or less X ab <math><msub><mi>X</mi> <mi>a</mi></msub><mi>b</mi></math>

Two things wrong with this: first the “b” would never be subscripted in LaTex, and second, two variables should not be lumped in the same <mi></mi> element because this causes MathML to set them in upright rather than italic type. So each variable really needs to be in its own <mi></mi>

 
posted 5 years ago
jl344 4 posts

Forum: Instiki – Topic: How could I preview/undo changes?

Thanks! Nothing wrong with that at all, now that I see how it works. I did find the history after I’d been experimenting for more than half an hour. I’m glad I found this wiki.

 
posted 5 years ago
admin 58 posts

Forum: Instiki – Topic: How could I preview/undo changes?

Every page has a “History”, a “Diff” between successive Revisions, and the ability to Rollback to a prior Revision.

Instead of a Preview, successive edits, within 1/2 hour, by the same user, do not create a new Revision.

So save your work, as you go and you’ll be able to see your progress and still not lose anything (remember, with other wikis, changes which have been previewed, but not saved, will be lost).