ram

问题 How does the RAM required to store data in memory compare to the disk space required to store the same data in a file? Or is there no generalized correlation? For example, say I simply have a billion floating point values. Stored in binary form, that\'d be 4 billion bytes or 3.7GB on disk (not including headers and such). Then say I read those values into a list in Python... how much RAM should I expect that to require? 回答1: Python Object Data Size If the data is stored in some python object,

问题 I want to get full RAM size of a device. memoryInfo.getTotalPss() returns 0. There is not function for get total RAM size in ActivityManager.MemoryInfo. How to do this? 回答1: Standard unix command: $ cat /proc/meminfo Note that /proc/meminfo is a file. You don't actually have to run cat , you can simply read the file. 回答2: As of API level 16 you can now use the totalMem property of the MemoryInfo class. Like this: ActivityManager actManager = (ActivityManager) context.getSystemService(Context

问题 How does VBulletin get the system information without the use of exec ? Is there any other information I can get about the server without exec? I am interested in: bandwidth used system type CPU speed/usage/count RAM usage 回答1: Use PHPSysInfo library phpSysInfo is a open source PHP script that displays information about the host being accessed. It will displays things like: Uptime CPU Memory SCSI, IDE, PCI Ethernet Floppy Video Information It directly parsed parses /proc and does not use exec

问题 I am often confused with the concept of virtualization in operating systems. Considering RAM as the physical memory, why do we need the virtual memory for executing a process? Where does this virtual memory stand when the process (program) from the external hard drive is brought to the main memory (physical memory) for the execution. Who takes care of the virtual memory and what is the size of the virtual memory? Suppose if the size of the RAM is 4GB (i.e. 2^32-1 address spaces) what is the

问题 I would like to know how it is possible to set an upper limit on the amount of memory MySQL uses on a Linux server. Right now, MySQL will keep taking up memory with every new query requested so that it eventually runs out of memory. Is there a way to place a limit so that no more than that amount is used by MySQL? 回答1: MySQL's maximum memory usage very much depends on hardware, your settings and the database itself. Hardware The hardware is the obvious part. The more RAM the merrier, faster

问题 I need to check CPU and memory usage for the server in java, anyone know how it could be done? 回答1: If you are looking specifically for memory in JVM: Runtime runtime = Runtime.getRuntime(); NumberFormat format = NumberFormat.getInstance(); StringBuilder sb = new StringBuilder(); long maxMemory = runtime.maxMemory(); long allocatedMemory = runtime.totalMemory(); long freeMemory = runtime.freeMemory(); sb.append("free memory: " + format.format(freeMemory / 1024) + "<br/>"); sb.append(

问题 What\'s your preferred way of getting current system status (current CPU, RAM, free disk space, etc.) in Python? Bonus points for *nix and Windows platforms. There seems to be a few possible ways of extracting that from my search: Using a library such as PSI (that currently seems not actively developed and not supported on multiple platform) or something like pystatgrab (again no activity since 2007 it seems and no support for Windows). Using platform specific code such as using a os.popen(\