I frequently hear that cin is significantly slower than scanf in C++. Is this true? And how to improve the efficiency of cin? It is really nice to use most of time. One discussion about that cin is very slow is here: http://apps.topcoder.com/forums/?module=Thread&threadID=508058&start=0&mc=7 In short: cin is not always slower (can be faster actually, see…
I am writing a OCaml program but want to call some C functions provided in some source code or library. How to achieve this? Is there any good tutorials on this? A very good tutorial that is easy to follow and understand: How to wrap C functions to OCaml. A comprehensive reference manual: Chapter 19…
What is the length of int in OCaml? It is said that int in OCaml is 31. But I get this: # (1 lsl 33);; – : int = 8589934592 8589934592 is larger than 2^31. On my laptop (64-bit Fedora Linux), the int in OCaml is 63 bits. The code (count1s counts the number of…
Which ones are good systems conferences? Top ones by ACM and USENIX: OSDI: https://www.usenix.org/conferences/byname/179 SOSP: http://sosp.org/ Other SIGOPS Events: http://www.sigops.org/conf-sponsored.html EuroSys: http://www.eurosys.org/ SoCC: http://www.socc2013.org/ (SoCC 2013) ASPLOS: http://www.sigplan.org/Conferences/ASPLOS/Main VEE: http://www.sigplan.org/vee.htm USENIX ATC: https://www.usenix.org/conferences/byname/131 NSDI: https://www.usenix.org/conferences/byname/178 IEEE Conferences: ICDCS: http://www.temple.edu/cis/icdcs2013/ (2013) IPDPS: http://www.ipdps.org/ Other related ones and workshops: HPCA: Search HPCA ConferenceSC: http://www.supercomp.org/IEEE CLUSTER: http://www.clustercomp.org/ HotCloud:…
I want to learn transactional memory technologies. Any suggestions on Transactional memory learning materials? Thanks! I highly suggest the Transactional Memory lecture by James R. Larus and Ravi Rajwar of Synthesis Lectures on Computer Architecture: The Transactional Memory lecture:http://www.morganclaypool.com/doi/abs/10.2200/S00070ED1V01Y200611CAC002 Link to the PDF:http://www.morganclaypool.com/doi/pdf/10.2200/S00070ED1V01Y200611CAC002
Which are the consistency models used for distributed systems? Papers that survey the consistency models Robert C. Steinke and Gary J. Nutt. 2004. A unified theory of shared memory consistency. J. ACM 51, 5 (September 2004), 800-849. DOI=10.1145/1017460.1017464 http://doi.acm.org/10.1145/1017460.1017464 David Mosberger. 1993. Memory consistency models. SIGOPS Oper. Syst. Rev. 27, 1 (January 1993), 18-26. DOI=10.1145/160551.160553…
How to set Google Chrome’s proxy settings in command line on Linux? I am using Google Chrome on Linux and start it by google-chrome. How can I set the proxy using the command line? It tell me that my desktop is not supported but I can set the proxy in command line. Use the –proxy-server…
How to Sync the Contacts in My iPhone with Google Gmail Account? To sync your Google contacts, one good method is using CardDAV. You’ll be able to edit, add, and remove contacts from your device and keep them in sync with your Google Gmail account. It is straightforward: Open the Settings application on your device….
How to add Google Custom Search to Question2answer? I do not want to create / edit / use a advanced theme. What I prefer is a plugin to replace the default search module with Google Custom Search. Thanks! Check out the Google Custom Search plugin: Google Custom Search plugin This site use it and it…
How to restore a Gnome 3 session? Which means: opening all the programs running last time when I log out in Gnome 3. If your purpose is to automatically start programs after logging in Gnome, another possible method is using the autostart script: https://www.systutorials.com/qa/119/how-to-write-a-autostart-script-for-gnome Run gnome-session-properties. In the “Options” tab, select “Automatically remember running applications…
What I want is to just restart Gnome 3 only and not to close and reopen the programs running. Thanks a lot! Just run r in Gnome 3’s “Run command” Box: Alt + F2, then enter r and hit Enter. Gnome 3 will restarts itself only.
What are the popular / good NoSQL databases nowadays? MongoDB, CouchDB Find more at https://en.wikipedia.org/wiki/NoSQL and http://nosql-database.org/ Answered by omshivaprakash.
It is painful for a Linux user to use the OCaml toplevel without the readline features. Is there a method to enable/add these kinds of features in readline to the OCaml toplevel? I find 2 options that work very well for me: utop provides a beautiful interface and supports completion, colors, parenthesis matching, etc. It…
iPhone has the touch screen. Is is possible to turn my iPhone to a wireless mouse on Linux? Use the WiFi Mouse app/server: http://wifimouse.necta.us/ First, install the WiFi Mouse app on you iPhone: https://itunes.apple.com/app/id591076411?mt=8 Second, install the WiFi Mouse server downloaded from http://wifimouse.necta.us/ If you are using Fedora Linux, you need to convert the .deb…
I come across some closed source software that only provides .deb packages. Fedora manages packages with rpm/yum. How to install the .deb packages on Fedora? Alien is a tool to convert .deb package to .rpm package: http://joeyh.name/code/alien/ In latest Fedora, the tool alien is in Fedora’s repository. You can use dnf to install the package….
Chrome reads the proxy settings from Gnome correctly. However, when I run Chrome under KDE, the proxy integration is broken: In the settings of Chrome, clicking the “Change proxy settings” opens the KDE proxy setting dialog correctly (the command kcmshell4 proxy actually is executed). However, after the proxy settings are made, Chrome does not read…
How To Find Out When Photos in The iPhone Were Taken? The default viewer in iPhone seems do not show these information. The iPhone has no native mechanism to see the photo taken date information. However there is the information. You need a 3’rd party application to view the EXIF data (time taken, GPS coordinates,…
What are the SQL layer solution over NoSQL databases such as key/value stores? Phoenix: A SQL layer on HBase: https://github.com/forcedotcom/phoenix They also show some performance results: https://github.com/forcedotcom/phoenix/wiki/Performance F1 – The Fault-Tolerant Distributed RDBMS Supporting Google’s Ad Business: http://research.google.com/pubs/pub38125.html With F1, we have built a novel hybrid system that combines the scalability, fault tolerance, transparent sharding,…
How to add an existing user to an existing group in Linux? We can use usermod to change/add user group for users. # usermod -a -G group_name user_name -a, –append Add the user to the supplementary group(s). Use only with the -G option. -G, –groups GROUP1[,GROUP2,…[,GROUPN]]] A list of supplementary groups which the user is…
How to add the social share icons to q2a as shown in this site? This site uses the Question2Answer Share plugin: https://github.com/NoahY/q2a-share After installing the plugin by downloading and copying the directory for the plugin to the qa-plugin directory, you can select the networks to share to in ‘Admin -> Plugins’. I see. Thanks!