%title TOP %title Version 3.6.1 %center William LeFebvre %center with much help from others %title Frequently Asked Questions and their Answers %TOC %section General %question What is top? %answer Top provies the user with a regularly updated display showing information about the system and its top cpu-using processes. Think of it as a full-screen "ps" output that gets updated at regular intervals. %question Where do I get the latest version of top? %answer The official site for top is "ftp.unixtop.org" in the directory "/pub/top". Top is also a SourceForge project, and the most recent releases are available on any of the SourceForge mirrors. The SourceForge project page is at http://sourceforge.net/projects/unixtop. %question Is there a web page for top? %answer Yes. Point your browser at http://www.unixtop.org. It includes all documentation, a nice interactive display which describes the various components of the output of top, web-based retrieval of the package, year 2000 information, and other neat stuff. %question Is there a mailing list or on-line bulletin board for top? %answer There is a mailing list used for general announcements regarding top, including new releases. This mailing list is available to sourceforge members and can be accessed from the unixtop sourceforge project page. Visit SourceForge and search for the project "unixtop", then click on "mailing lists". There are also on-line forums available through SourceForge where members can post questions and comments. %question What about Year 2000 compliance? %answer Top did not experience any problems with the transition to the year 2000. A full statement concerning top and the year 2000 can be found in the file "Y2K" included with the distribution. %question Will there be another major release of top? Will there be a top version 4? %answer I have some great ideas for the next major release of top, and I very much want to make those ideas a reality. What I don't have much of these days is free time. But I will keep poking at it and I hope to have top version 4.0 ready by the fall of 2006. %question Does top really support multi-processor systems? %answer On platforms that support multiple processors, top is able to detect and correctly summarize the information about those processors. What top does not do is break down the cpu states summary (the third line of the display) by cpu. Instead it collects the cpu state information from all processors and combines them in to a single line. Some vendors include a modified version of top that presents this information for each cpu. Top 3.7 may have this functionality but it is not present in the standard top 3.6 release. %question Is top under CVS control? Can I access the sources via SourceForge CVS or Subversion? %answer I maintain top using subversion, not CVS. Although I utilize my own private subversion repository, it is regularly mirrored in to the SourceForge Subversion repository. You can access the SourceForge repository here: https://svn.sourceforge.net/svnroot/unixtop. %section Compiling %question We just upgraded our operating system to a new version and top broke. What should we do? %answer Recompile it. Top is very sensitive to changes in internal kernel data structures. It is not uncommon for a new version of the operating system to include changes to kernel data structures. %section Running %question I just finished compiling top and it works fine for root, but when I try to run it as a regular user it either complains about files it can't open or it doesn't display all the information it should. Did I do something wrong? %answer Well, you're just not done. On many operating systems today, access to many of the kernel memory devices and other system files is restricted to either root or a particular group. The configure script figures this out (usually) and makes sure that the "install" rule in the Makefile will install top so that anyone can run it successfully. However, you have to %em{install} it first. Do this with the command "make install". %question Top is (not) displaying idle processes and I don't (do) want it to. %answer This default has only changed about a dozen times, and I finally got tired of people whining about it. Go read the manual page for the current version and pay special attention to the description of the "TOP" environment variable. %question We have so much memory in our machine that the memory status display (the fourth line) ends up being longer than 80 characters. This completely messes up top's output. Is there a patch? %answer Most modules have been changed to use new memory formatting functions which will display large values in terms of megabytes instead of kilobytes. This should fix all occurences of this problem. Also note that newer versions of top can use columns beyond 79, and understand window resizes. So you can always make your window wider. %question I tried to compile top with gcc and it doesn't work. I get compilation errors in the include files, or I get an executable that dumps core, or top displays incorrect numbers in some of the displays. What's wrong? %answer Gnu CC likes very much to use its own include files. Not being a gcc expert, I can't explain why it does this. But I can tell you that if you upgrade your operating system (say from Solaris 2.6 to Solaris 2.7) after installing gcc, then the include files that gcc uses will be incorrect, especially those found in the "sys" directory. Your choices are: (1) rebuild and reinstall the "standard" include files for gcc (look for scripts in the distribution called "fixincludes" and "fixinc.svr4"), (2) compile machine.c with "CFLAGS=-I/usr/include" then make the rest of the object files normally, or (3) use a different compiler. %question The cpu state percentages are all wrong, indicating that my machine is using 95% system time when it is clearly idle. What's wrong? %answer This can happen if you compiled with gcc using the wrong include files. See the previous question. %section MacOSX Problems %question I tried to configure top on my Mac OSX system and I got an error claiming "macosx not supported". What up? %answer Since I don't have full time root access to a Mac OSX system I cannot provide effective support for the platform. MacOSX uses Mach, and it is very difficult to extract accurate system and process information from the system. It takes a lot of trial and error, along with root access. I have included the most up-to-date version of the macosx module in the distribution, but I do not claim that it works. If you want to try to use it, you can configure with "./configure --with-module=macosx". %section SunOS Problems %question I tried compiling top under SunOS version 4.1.x and it got compile time errors or run time errors. Is there a patch? %answer If you try compiling top in a "System V environment" under SunOS (that is, /usr/5bin is before /usr/bin on your path) then the compilation may fail. This is mostly due to the fact that top thinks its being compiled on a System V machine when it really isn't. The only solution is to put /usr/bin and /usr/ucb before /usr/5bin on your path and try again. %section Solaris Problems %answer NOTE: the most common source of problems with top under Solaris is the result of compiling it with the wrong front end. Make sure that /usr/ucb is not on your path before attempting to compile top under Solaris. %question Is there somewhere I can get a pre-compiled package? %answer Yes. Although I don't provide pre-compiled binaries, you can get a Sun-style package from www.sunfreeware.com. %question Under Solaris 2, when I type "make", the system says "language optional software package not installed." What's going on? %answer You tried to compile with /usr/ucb/cc. Make sure /usr/ucb is not on your path. Furthermore, you do not have a Sun compiler installed on your system. You need a compiler to make top. Either Sun's C compiler or the Gnu C compiler will work fine. %question Under Solaris 2, when I run top as root it only shows root processes, or it only shows processes with a PID less than 1000. It refuses to show anything else. What do I do? %answer You probably compiled it with /usr/ucb/cc instead of the real C compiler. /usr/ucb/cc is a cc front end that compiles programs in BSD source-level compatability mode. You do not want that. Make sure that /usr/ucb is not on your path and try compiling top again. %question Under Solaris 2, I compiled top using what I am sure is the correct compiler but when I try to run it it complains about missing dynamic libraries. What is wrong? %answer Check to see if you have LD_LIBRARY_PATH defined in your shell. If you do, make sure that /usr/ucblib is not on the path anywhere. Then try compiling top again. %question Under Solaris 2, when I try to run top it complains that it can't open the library "libucb.so.1". So I changed the LIBS line in m_sunos5.c to include -R/usr/ucblib to make sure that the dynamic linker will look there when top runs. I figured this was just an oversight. Was I right? %answer No, you were not right. As distributed, top requires no alterations for successful compilation and operations under any release of Solaris 2. You probably compiled top with /usr/ucb/cc instead of the real C compiler. See FAQ 22 for more details. %question On my 64-bit system some processes show up with incorrect information (such as zero memory). %answer %mark{64bit} If you are running a 64-bit system, then you will want to make a 64-bit top binary. Top's configure script attempts to detect 64-bit systems, and will adjust the compilation options accordingly. If you configure and make a binary on a 32-bit system it will still run on a 64-bit system, but may not produce the correct results. The same will happen if you configure your distribution on a 32-bit system then compile with that configuration on a 64-bit system. You must configure and compile on the same system. %question Can I install both 32-bit and 64-bit binaries on a central file server and have machines which mount it automatically use the correct one? %answer Yes. First, compile a 32-bit version and name it top32. Then compile a 64-bit version (see FAQ #%ref{64bit}) and name it top64. Make sure each binary has the correct ownership and mode. Choose your bin directory (we will refer to that as $BIN). In $BIN make sure there are subdirectories named "sparcv7" and "sparcv9". If they don't exist then create them. Copy "top32" to "$BIN/sparcv7/top" and "top64" to "$BIN/sparcv9/top". Finally copy (do not link) the binary /usr/lib/isaexec to "$BIN/top". When a user runs "top" she will actually be running a copy of isaexec. This tool will automatically determine the kernel type and run the top "binary" out of the correct subdirectory. %question This version of top show less available swap space than previous versions. Why does it no longer match the output of the swap summary produced with "swap -s"? %answer Starting with version 3.6 of top, the amount of swap space reported by top has been changed to reflect only disk-based swap space. The swap summary produced with "swap -s" also include memory-based swap space. This changed was mae for several reasons. It makes the display under Solaris more like those of other operating systems. The display is more what users expect (except those used to previous versions of top). Most importantly, "swap -s" gets its data via an undocumented system interface. Now that top no longer displays that data it can use publically documented and maintained system interfaces to retrieve its data. %section SVR4-derived Problems %question When I run top on my SVR4-derived operating system, it displays all the system information at the top but does not display any process information (or only displays process information for my own processes). Yet when I run it as root, everything works fine. What's wrong? %answer Your system probably uses the pseudo file system "/proc", which is by default only accessible by root. Top needs to be installed setuid root on such systems if it is going to function correctly for normal users. %section SVR42 Problems %question The memory display doesn't work right. Why? %answer This is a known bug with the svr42 module. The problem has been traced down to a potential bug in the "mem" driver. The author of the svr42 module is working on a fix. %section Still Stuck %question I'm still stuck. To whom do I report problems with top? %answer The most common problems are caused by top's sensitivity to internal kernel data structures. So make sure that you are using the right include files, and make sure that you test out top on the same machine where you compiled it. Sun's BSD Source Compatability Mode is also a common culprit. Make sure you aren't using either /usr/ucb/cc or any of the libraries in /usr/ucblib. Finally, make sure you are using the correct module. If there does not appear to be one appropriate for your computer, then top probably will not work on your system. If after reading all of this file and checking everything you can you are still stuck, then please use SourceForge to submit a support request or a bug. Top is supported by the SourceForge project named "unixtop". On SourceForge you will find defect tracking, a mailing list, and on-line forums. You can also contact the author through SourceForge.