I don't won't to use swap file (due to some bug in kernel or AMD driver).  I wan't to have some util running and monitoring free system memory and alerting me when it becomes less than some specified limit.  This will notify me that I need to close some applications (or browser tabs) to avoid system freeze due to some strange kswapd0 I/O activity (probably another bug).  Is there any appropriate software?  UPDATE:  I've redesigned script provided by Gary for my need and want to share it  #!/bin/bash  #Minimum available memory limit, MB THRESHOLD=400  #Check time interval, sec INTERVAL=30  while : do      free=$(free -m|awk '/^Mem:/{print $4}')     buffers=$(free -m|awk '/^Mem:/{print $6}')     cached=$(free -m|awk '/^Mem:/{print $7}')     available=$(free -m | awk '/^-\/+/{print $4}')      message="Free $free""MB"", buffers $buffers""MB"", cached $cached""MB"", available $available""MB"""      if [ $available -lt $THRESHOLD ]         then         notify-send "Memory is running out!" "$message"     fi      echo $message      sleep $INTERVAL  done
This is a follow-up to : ulimit and cgroups are not user friendly, and besides, wouldn't work with applications that spawn separate processes, such as Chrome/Chromium for each new (group of) tabs.  The simple and effective solution, used by Windows 7 actually, is to warn the user that the OS is running low on memory. This simple warning pop-up has prevented me from having any low-memory-caused system freeze in Windows, while I kept running into them on Ubuntu distros that I was testing live (where the RAM-mounted disk would eat up 2GB alone).  So, is there some way to automatically warn the user that the available RAM is nearing zero, without the user having to keep an eye on some memory monitoring gadget? Surely  could be configured to do that?
Basically on my site I have a bunch of song lyrics and in a static page I want to show them listed by album  and album position of the song and I have two custom fields with that data, sd_album_title and `sd_album_track_n. Plus some of the songs don't have an album yet, so both values are void, and I wish to list those ones at the foot of the others, sorted by alphabetical order.  The latest thing I tried at least to sort everything by the two field is this one:  $key = 'sd_album_title'; $themeta = get_post_meta($post-&gt;ID, $key, TRUE);  add_filter( 'pre_get_posts', 'my_get_posts' ); function my_get_posts( $query ) {     if ($themeta != '') {         $query-&gt;set( 'post_type', 'lyric' );         $query-&gt;set( 'meta_key', 'sd_album_title' );         $query-&gt;set( 'orderby', 'meta_value' );         $query-&gt;set( 'order', 'ASC' );         $query-&gt;set( 'meta_query', array(               array(                     'key' =&gt; 'sd_album_title'               ),               array(                     'key' =&gt; 'sd_album_track_n',                     'value' =&gt; 'target_value',                     'compare' =&gt; '&gt;=',                     'type' =&gt; 'numeric'               )         ));     }     return $query; }  $getlist= 'my_get_posts'; $posts = get_posts( $getlist );   And my intention was to put an else at the end of it with an array ordered by title for the other songs, but it returns nothing as it is. Could something like this work with some corrections or am I on a totally wrong path? I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}? Normal subgroups of dihedral groups How can I search tags on StackOverflow Careers? I am attempting to search jobs by tag on StackOverflow Careers. On SO, this is done using square brackets, but that is simply doing a keyword search, and I still get results that don't have the tag I am looking for.  For example, when I search for the keyword "android", I get this:        which is the same as when I search for the keyword "[android]":        Is there a format I can use to search jobs by tag? If not, I believe this would be a nice feature (seems intuitive for the Stack Exchange invite-only job site). Sometimes it takes too long for the network manager to update to see new wireless AP. Is it possible to change the time interval between checks? Does a creature with Lifelink provide lifegain equal to its power, or the defender's toughness? Setup IIS 7.5 with multiple website bindings and SSL? On IIS 7.5 I am trying to achieve this with two websites:  Default Web Site is bound to:  (blank host header port 80 - http) (blank host header port 443 - https) go.example.com www71.example.com the IP address of go.example.com  2nd web site "Beta" is bound to:  beta.example.com (blank host header port 443 - https) * using blank only because it doesn't seem to be possible to    bind https to a named host header   And both need to work with SSL.  But I have these problems:   When I type in beta.example.com, I see the go.example.com site instead I can not seem to add the SSL binding to both websites at once (I have a single *.example.com wildcard certificate).  The beta site will not even start if I add the https binding to it.   This is how I have set it up:    What is the correct way to set it up? Why is the relationship between atomic number and density not linear? How to add startup applications in lubuntu? Is there a 'Startup applications' app for lubuntu? Or how do I add apps to startup? I attempted a tutorial to add entries to ~/.config/autostart, but it did not work. Isn't there an easy way? Any ideas please? Unwanted faint lines connecting dashed double line Building on the answer  by wrtlprnft, I have the following code     \documentclass[tikz,margin=1cm]{standalone}    \usetikzlibrary{decorations.markings}    \begin{document}    \begin{tikzpicture}         \tikzstyle{arrowed double line}=[             dashed, double distance between line centers=3pt,             postaction=decorate,             decoration={                 markings,                 mark=between positions 10pt and -10pt step 20pt with {                     \arrow[thin,yshift= 1.5pt,xshift=.8pt]{&gt;}                     \arrow[thin,yshift=-1.5pt,xshift=.8pt]{&lt;}                 },             },         ]         \draw[arrowed double line] (0,0) --  (1,2);     \end{tikzpicture} \end{document}   which produces this:    I am unhappy with the faint transverse lines between the dashes. I don't even know why tikz decides to draw them.  Is there a way to get rid of them?  Thanks in advance to all replies.  PS the same thing occurs at the caps of double solid lines How do I solve this limit: $\lim _{x \to 0} \left(\frac{ \sin x}{x}\right)^{1/x}$? Applications of ultrafilters I'm looking for some interesting applications of ultrafilters and also everything of interest involving ultrafilters. Do you know some applications or interesting things involving ultrafilters?  I'm at the beginning, so I'd prefer some applications that also a beginner could read. File access time not updating in ubuntu 12.04 Let $V$ be a representation with character $\chi$.  I would like to have a formula for the characters of the representations $\mathrm{Sym}^m[V]$ and $\wedge ^m[V]$ in terms of $\chi$.  Fulton and Harris presents such a formula for $m=2$, but not for general $m$.  Is there a "nice" such expression?  I found a paper by , but this doesn't seem to be what I'm looking for (it doesn't seem to give a general formula in terms of $\chi$).  In case the link does not work, here is the reference:  X. Zhou, P. Pulay. Characters for Symmetric and Antisymmetric Higher Powers of Representations: Application to  the  Number of Anharmonic Force Constants in Symmetrical Molecules. Journal of Computational Chemistry, Vol 10, Issue 7, (1989). Animation Cycles rendering remains incredible slow How do you change age settings on ROBLOX? How do you set your age settings on ROBLOX if you accidentally set to under 13? I accidentally put 2008 instead of 1998 in the sign up section. Is there any way to change this, as in settings, age settings are greyed out. How can I make a hexagonal grill? How would I be able to create a grill of sorts found on the front of some computer cases such as this one Finding the limit $\displaystyle\lim_{x\to 0+} \left(\frac{\sin x}x\right)^{1/{x^2}}$ Find the following limit: $$\displaystyle\lim_{x\to 0+} \left(\frac{\sin x}x\right)^{1/{x^2}}$$   Well I tried to do the $\exp\left(\frac{ \ln\frac{\sin x}{x}}{x^2}\right)$ then apply LHR but I seem to get to endless dervivations...   There's got to be a more simple approach. What does the operator "<<" mean in C#? Where are my Screenshots? I pressed F2 to take a few Minecraft screenshots. Later I couldn't find them. Where are they stored on my computer?