Drupal 8 performance regressions. Would it be a solution for high traffic online communities? There were some legitimate concerns about Drupal 8 potential performance regressions as a result of being built on top of Symfony2. Drupal 8 Beta-14 is the latest release; It seems that the Drupal 8 big release it comes apace. As per all the benchmarks I saw until I noticed that Drupal 8 is much slower than Drupal 7 especially for logged in users which is kind of a bummer.   Isn't Drupal supposed to be used for online communities where logged in users could interact? For displaying news and blogs there are already other software much convenient to use such as Wordpress. What kind of server would support such an expensive product? In this scenario, will be Drupal 8 a solution for high traffic online communities where logged-in users could post things and make comments and interact with each other?  Shouldn't this newer version of Drupal better than the old one? In terms of performance it doesn't seems so. This is why I'm thinking to find alternatives to Drupal for my potential clients. I'm not sure that financially speaking would worth to develop an online community website in Drupal and pay a lot for hosting and development.
Are there any performance comparisons? Are there any reliable performance comparisons between vanilla Drupal 8 versus Drupal 7?  I have searched the web but only find the post "", which is far from encouraging.
Right-click on Touchpad not working after update to 18.04 LTS I have a Lenovo Yoga 910-13IKB. I was running Ubuntu 17.10 with no issues. I upgraded to 18.04 LTS and now my right-click on my touchpad does not register. I can only left-click.  I already tried the steps listed , but they did not fix the issue.  Does anyone know how to fix this?  Thanks. What Hogwarts classes are taught to two houses at once? I remember from my mumble about nine mumble rereads of the Harry Potter series that the following classes Harry took were taught to more than one house in the same lesson:   Potions with the Slytherins  Herbology with the Hufflepuffs  Care of Magical Creatures with the Slytherins  broomstick riding with at least the Slytherins (maybe other houses, too?)    I don't remember any student from a house that isn't Gryffindor being mentioned in the sections on Transfiguration, Charms, Defense Against Dark Arts, History of Magic, or Divination. That would mean McGonagall had to teach twice as many classes as Snape, if both subjects got the same number of lessons (which I think I recall).   Were any subjects other than Potions, Herbology, and Care of Magical Creatures taught to more than one house in the same lesson? And do we know why some subjects are taught to more students at the same time than others? Suppose I have a complex figure made ​​with TikZ. How do I use it several times without having to repeat all the commands?  \documentclass{article} \usepackage[utf8]{inputenc} \usepackage{tikz}  \begin{document}  Base figure  \begin{tikzpicture}   \draw[blue] circle (2);   \foreach \i in {0,10,...,350}     \draw[blue] (\i:1.9) -- (\i:2.1); \end{tikzpicture}  Using base figure.  \begin{tikzpicture}   \draw[blue] circle (2);   \foreach \i in {0,10,...,350}     \draw[blue] (\i:1.9) -- (\i:2.1);   \foreach \i in {0,10,...,350}     \node at (\i:2.7) {\tiny $\i^\circ$}; \end{tikzpicture}  Using base figure.  \begin{tikzpicture}   \draw[blue] circle (2);   \foreach \i in {0,10,...,350}     \draw[blue] (\i:1.9) -- (\i:2.1);   \foreach \i in {0,10,...,350}     \draw (0,0) -- (\i:2); \end{tikzpicture}  \end{document} Proving of Integral $\int_{0}^{\infty}\frac{e^{-bx}-e^{-ax}}{x}dx = \ln\left(\frac{a}{b}\right)$ Prove that      $$ \int_{0}^{\infty}\frac{e^{-bx}-e^{-ax}}{x}\,dx = \ln\left(\frac{a}{b}\right) $$   My Attempt:  Define the function $I(a,b)$ as  $$ I(a,b) = \int_{0}^{\infty}\frac{e^{-bx}-e^{-ax}}{x}\,dx $$  Differentiate both side with respect to $a$ to get  $$ \begin{align} \frac{dI(a,b)}{da} &amp;= \int_{0}^{\infty}\frac{0-e^{-ax}(-x)}{x}\,dx\\ &amp;= \int_{0}^{\infty}e^{-ax}\,dx\\ &amp;= -\frac{1}{a}(0-1)\\ &amp;= \frac{1}{a} \end{align} $$  How can I complete the proof from here? mysql-server-5.7 package post-installation script subprocess returned error exit status 127 I have a website server on Ubuntu server 18.04 with apache and mysql. The database stopped for no apparent reason. I just did a restart of mysql server to solve the issue but after a simple update I got some errors on mysql-server package. The update was for other packages and not mysql-server package. Mysql still stops at least once a week and each time I have to restarts the mysql-server.  Can some one help me to understand the error please ?  Here the result of: dpkg --configure -a  Configure mysql-server-5.7 (5.7.23-0ubuntu0.18.04.1) ... /var/lib/dpkg/info/mysql-server-5.7.postinst: ligne 191: /usr/share/mysql-common/configure-symlinks: no file or folder  dpkg: erreur de traitement du paquet mysql-server-5.7 (--configure) : installed mysql-server-5.7 package post-installation script subprocess returned error exit status 127 In Windows 8, when Alt+Tab, the desktop would appear as an option to switch to at the end of the list of open programs (thus Alt-Shift-Tab helpfully took you right to the desktop).  In Windows 10 that desktop option is gone. Is there any way to get it back?  I know about Windows+D but Alt+Tab is just more convenient in my opinion. And  also has no desktop and is uglier. I want to untriangulate every object in my scene with this script:  import bpy  for ob in bpy.data.objects:     bpy.ops.mesh.tris_convert_to_quads(limit=0.9, uvs=False, vcols=False, sharp=False, materials=False)   But it doesn't work in object mode, any ideas on how I can get it working? Prove a assertion concerning Lebesgue space Let $f_n \in L^1$ such that $f_n\rightrightarrows f$. Then I want to conclude that If $\mu(X)&lt;\infty,$ then $f\in L^1$ and $\int f_n\to\int f$, so I want to make use of the Dominated convergence theorem, the thing is that I don't know which would be my dominating function.  I was trying to figure out if the measure could play that role, but after thinking a little bit I have realize that the measure doesn't have to be bigger than the absolute value of the functions of the sequence.  Another thing I was thinking of, is to apply Fatou's lemma, but I can't ensure that my functions are positive.  So, Can someone help me to prove this theorem please ?  Thanks a lot in advance :).    NOTE: I think this theorem is taken from Folland's Real analysis, modern techniques, and their aplications 2nd Edition :), This is to have all the definitions so we can talk the same language as in the book (this is, same notation and theorems or machinery) Is there a preinstalled or automatic firewall? Does Ubuntu come with a preinstalled or automatic firewall? If not, do I need one?   I've read some articles about the advantages of Linux over other operating systems about security (no need to have antivirus, ...) but would like to be sure. How to capture the scale of a scene? My framing in the following photo completely failed to capture the sheer height of the waterfall.  If you don't know I was standing at the top of the waterfall, and the "splinters" at the bottom are full-size tree trunks 2 feet in diameter, you wouldn't have a clue how tall it is.  It just looks like a smaller, shorter waterfall shot with a slower shutter speed.    My question isn't about this picture or waterfalls in particular, but about framing to capture the scale of your subject in general.  What are techniques to show just how big something really is?  Or conversely, something really small?  Especially things like rocks or water that look roughly the same at any size. I have to do proof of $(a+b)^n$ and $(a+b)^{n+1}$ with mathematical induction.  I finished the first one $(a+b)^n = a^n + na^{n-1}b+\dots+b^n$.  I however have trouble with the second one, I don't know what to start exactly. Any help/hints? $\int_{\frac{1}{3}\pi}^{\frac{2}{3}\pi} {\sin(x)\;dx}$ using Riemann sums? How to change the default views of quad view? How do I change the TOP ortho view to BACK ortho view for my BACK image?   check out the pic I uploaded to see what I'm talking about. How do I unit test (using xUnit) a class that has internal private methods, fields or nested classes? Or a function that is made private by having  (static in C/C++) or is in a private () namespace?  It seems bad to change the access modifier for a method or function just to be able to run a test. Human & Alien captured, observed by higher beings From a collection of short stories I read at least 30 years ago. :/  This is going to be incredibly vague, so apologies in advance.  A human and alien (blob/octopus-like...I think) from warring races are captured by an unidentified higher intelligence and put in an enclosure (more like a zoo habitat rather than a prison cell). They are separated by an invisible barrier and can see each other.  I think they were both trying to escape or trying to figure out how they could kill the other first. There was a bulldozer/loader type vehicle they could use at one point to build a shelter (or something).  I believe they were crafting makeshift weapons as well. There was no communication between the two as far as I remember.  The main tension in the story seemed to be was the race to get to the other first.  This has been stuck in my head forever. I know its a very common theme.  The short stories may have included Asimov. Alpha and Omega limit sets (dynamical systems) What are all the possible $α$- and $ω$-limit sets of points for the linear system of equations $x'=Ax$ given by the following matrices $A$:  I guess I don't really know how to get started, Could I have some guidance? So I was told to calculate the eigenvalues (fine) and eigenvectors (I kind of forgot how to do that...)  I know that the $ω$-limit sets of points are the set of points that the system of equation approach as time goes to infinity, and the $α$-limit sets of points are the points approached as t goes to negative infinity.   $    A=   \left[ {\begin{array}{cc}    -4 &amp; -2 \\    3 &amp; 11 \\   \end{array} } \right] $   $λ_1=-10$ $λ_2=-5$  Since both eigenvalue are negative, this is a stable node, and the $ω$-limit set=0.  for $λ_1=-10$:  eigenvector $    =   \left[ {\begin{array}{cc}   1 \\    3 \\   \end{array} } \right] $  for $λ_2=-5$:  eigenvector $    =   \left[ {\begin{array}{cc}   2 \\    1 \\   \end{array} } \right] $   $    A=   \left[ {\begin{array}{cc}    1 &amp; 1 \\    3 &amp; 1 \\   \end{array} } \right] $   $λ_1=4$ $λ_2=-2$  Since one eigenvalue is positive and one is negative, it is not stable, so I can't use the same reasoning that I used above to find the $ω$-limit set... so I am not sure how to continue  for $λ_1=4$:  eigenvector $    =   \left[ {\begin{array}{cc}   1 \\    1 \\   \end{array} } \right] $  for $λ_2=-2$:  eigenvector $    =   \left[ {\begin{array}{cc}   -1 \\    1 \\   \end{array} } \right] $   $    A=   \left[ {\begin{array}{cc}    4 &amp; 5 \\    -5 &amp; -2 \\   \end{array} } \right] $   $λ_1=1+4i$ $λ_2=1-4i$  for $λ_1=1+4i$:  eigenvector $    =   \left[ {\begin{array}{cc}   -3/5-(4i)/5 \\    1 \\   \end{array} } \right] $  for $λ_1=1-4i$:  eigenvector $    =   \left[ {\begin{array}{cc}   -3/5+(4i)/5 \\    1 \\   \end{array} } \right]$ How to make equally sized windows in corners of the screen? I have a  repository which contains a number of subdirectories. Now I have found that one of the subdirectories is unrelated to the other and should be detached to a separate repository.  How can I do this while keeping the history of the files within the subdirectory?  I guess I could make a clone and remove the unwanted parts of each clone, but I suppose this would give me the complete tree when checking out an older revision etc. This might be acceptable, but I would prefer to be able to pretend that the two repositories doesn't have a shared history.  Just to make it clear, I have the following structure:  XYZ/     .git/     XY1/     ABC/     XY2/   But I would like this instead:  XYZ/     .git/     XY1/     XY2/ ABC/     .git/     ABC/ An inequality from Littlewood's Miscellany The following code should find the appropriate project tag and remove it from the XmlDocument, however when I test it, it says:  The node to be removed is not a child of this node.  Does anyone know the proper way to do this?  public void DeleteProject (string projectName) {     string ccConfigPath = ConfigurationManager.AppSettings["ConfigPath"];      XmlDocument configDoc = new XmlDocument();      configDoc.Load(ccConfigPath);      XmlNodeList projectNodes = configDoc.GetElementsByTagName("project");      for (int i = 0; i &lt; projectNodes.Count; i++)     {         if (projectNodes[i].Attributes["name"] != null)         {             if (projectName == projectNodes[i].Attributes["name"].InnerText)             {                                                                 configDoc.RemoveChild(projectNodes[i]);                 configDoc.Save(ccConfigPath);             }         }     } }   UPDATE  Fixed. I did two things:  XmlNode project = configDoc.SelectSingleNode("//project[@name='" + projectName + "']");   Replaced the For loop with an XPath query, which wasn't for fixing it, just because it was a better approach.  The actual fix was:  project.ParentNode.RemoveChild(project);   Thanks Pat and Chuck for this suggestion.