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  • Reporting memory usage per process/program

    - by Nick Retallack
    How can I get the current memory usage (preferably in bytes so they can be added up accurately) for all running processes individually? Can I roll up the summaries for child processes into the process that spawned them? (e.g all apache threads together). Sometimes, my server runs out of memory and becomes unresponsive. I want to discover what is using up all the memory. Unfortunately, it's likely to not be a single process. Some programs spawn hundreds of processes, each using very little memory, but it adds up. On a side note, is it normal for apache to spawn 200+ processes?

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  • Fresh install CentOS 6.4 64b with directadmin slowly consumes all memory and crashes

    - by Coen Ponsen
    Dear server fault community, This is my first question on server fault, i'm new to server (mis)configuration so please forgive me for asking something stupid :) I'm running Directadmin on a CentOS 6.4 64b with 4GB memory and over 10000Gh virtual machine. I migrated my websites because my former vps couldn't keep up anymore. Only half of the websites from this 1GB machine were migrated jet. So the migration is still in progress and already my server crashes every day. The server performance up until that moment is perfect. The directadmin log files show nothing out of the ordinary. Yesterday only the mysql server crashed but it also crashed the entire machine before. The memory usage in DA seems to be normal: directadmin directadmin (pid 3923 22158 22159 22160 22161 22162 )8.75 MB dovecot dovecot (pid 3851 ) 47.8 MB exim exim (pid 1350 ) 1.29 MB httpd (pid 21525 21528 21529 21530 21531 21532 21546 21571 21742 21743 21744 )490.4 MB mysqld mysqld (pid 1299 ) 287.8 MB named named (pid 3807 ) 16.3 MB proftpd proftpd (pid 1481 ) 1.91 MB sshd sshd (pid 1173 21494 ) 5.16 MB Restarting services immediately frees up memory, but slowly over time the memory usage increases(about 24 hours to crash). The commands: # sync # echo 3 > /proc/sys/vm/drop_caches Will free al memory correct. I could just create a cronjob but it seems the wrong way around to me. I can't seem to pinpoint the cause. Any advices, references or tips are highly appreciated! Greetings, Coen edit: free -m : after drop_caches: total used free shared buffers cached Mem: 3830 735 3095 0 0 21 -/+ buffers/cache: 712 3117 Swap: 991 0 991 I'll post another one this evening.

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  • Google Chrome is running my system out of memory

    - by jasondavis
    I am running Windows 7 x64 with 12GB of RAM I often have multiple windows and a ton of tabs open. I use the extension Session Buddy to restore all my windows and tabs once the memory gets too high. So my 12gb of ram will get up to around 93% used because of Chrome, now I can close chrome down and restore the same amount of windows and tabs and it will only use about 25% of memory, it then over time increases back up to the 90% zone after several hours. It seems that when I close tabs, instead of freeing that memory up, it doesn't so that is why the huge increase of memory usage as new tabs are opened and closed it just adds up, this sounds like a huge bug in chrome. Just for an example I just re-booted my system, I only have 1 window with 4 tabs open and in the task manager, it shows 29 chrome.exe processes I then killed all chrome processes and opened a chrome window with just 1 tab, it made 27 chrome.exe processes. Is this an issue that others have? More importantly, is there a fix? UPDATE I just read that each plugin and extension creates a chrome.exe process, I then couunted 24 extensions so that helps explain a portion of the large processes. Still not sure about memory not being freed up though!

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  • MySQL Memory Limit Windows Server 2003

    - by Matt
    I am running MySQL 5.0.51a on Windows Server 2003 Standard Edition on an HP DL580 G4 with 3GB installed. One of my database tables has grown to 5.3 GB with an index file of 2.5 GB, which I believe is causing MySQL to be slow due to having to constantly load and unload the index file when updates are made to the table. The server itself seems to be performing OK because MySQL is only using about 500MB of memory (there are other apps running on the system, but MySQL uses the most memory). The table is fairly active with new records getting adding all during day but no deletes, ever. The MySQL server has up to 600 connections allowed, but only small number (10 or 20) would actually be writing to this table. I increased the memory limits in MySQL but since the max connections is so high I don't think I can give each connection 1GB without risking a problem. Is there some tuning that would let just certain connections get a lot of memory? So I have started to look for alternatives to avert the crisis I know is coming soon. Some of the options I have: Upgrade to Server 2003 Enterprise to install 64GB of memory. Question: would 32 bit MySQL be able to access more than 2GB? Would that be 2GB per thread? That would still be smaller than the index table size so it might not solve the problem completely, but it would be better than now. Upgrade to Server 200x 64 bit and MySQL 64 bit. Switch to a *nix 64 bit server. If anybody has suggestions for things to do in the meantime, opinions on which way to go, or other things that I have overlooked I would appreciate the help. Thanks

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  • Why is my browser using so much memory?

    - by Steve
    Hi. I've recently had problems with Firefox running very slowly when I have many tabs open; say 20 tabs. My whole system would slow down. I decided to give Google Chrome a try, and it started out fine. But lately I am finding that it too, slows down my whole system. Looking at Task Manager, chrome.exe is using about 250MB of memory in about 6 different entries in task manager. However, when I shut Chrome down, memory usage is reduced by about 600MB. How can this be? (shows drop in memory usage after ending Chrome.) When my system locks up with Chrome having many tabs open, it takes 10 seconds to load the Start Menu, 10 seconds to expand All Programs, and each folder and subfolder, and 30 seconds for the program to be highlighted under my mouse. It also takes 10 seconds to switch to Notepad. Why is Chrome appearing to use so much more memory than Task Manager indicates? Why is my pagefile being used when I have around 1.1GB of memory? Can I set Chrome to run in RAM and not in the pagefile? How can 20 tabs use 600MB? That's 30MB per tab. Thanks for your help.

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  • How to change memory for DomU runtime

    - by saffron
    I have a xen server with xen-4.1.3, linux-image-3.2.0-3-amd64, debian squeeze and 16Gb of RAM. The domain-0 has 1Gb of ram, the rest of memory belongs to the hypervisor. I want to start a guest domain with a minimal amount of memory and increase it runtime later. When I start a guest domain with 256Mb of ram and run xm mem-set domu 4Gb, I get ~3Gb only in domu and a guest domain free says: root@test:~# free total used free shared buffers cached Mem: 2830620 72868 2757752 0 2432 43504 -/+ buffers/cache: 26932 2803688 Swap: 1048572 0 1048572 And a guest domain dmesg says: [ 0.000000] Memory: 175912k/2883584k available (3527k kernel code, 448k absent, 2707224k reserved, 3210k data, 612k init) When I start a guest domain with 2Gb of ram I can run xm mem-set domu 7Gb and get ~7Gb of ram in a guest domain: root@test:~# free total used free shared buffers cached Mem: 6828228 74944 6753284 0 1328 12568 -/+ buffers/cache: 61048 6767180 Swap: 1048572 0 1048572 And a guest domain dmesg: [ 0.000000] Memory: 1674960k/16651264k available (3527k kernel code, 448k absent, 14975856k reserved, 3210k data, 612k init) How can I start a guest domain with a minimal amount of ram (256Mb) and increase it under 15Gb?

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  • Retrieve Heap memory size and its usage statistics etc...?

    - by AKN
    Lets say I open some application or process. Did some work with that. Now I closed it. Need to know whether this application caused any memory leak. i.e used up some heap memory and not cleared it properly. Can I get this statistics some how? I'm using Visual Studio (for development) under Windows OS. Even I would be interested in knowing this information for any 3rd party application.

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  • Where to check for heap memory size and its usage statistics etc... in windows?

    - by AKN
    Lets say I open some application or process. Did some work with that. Now I closed it. Need to know whether this application caused any memory leak. i.e used up some heap memory and not cleared it properly. Can I get this statistics some how? I'm using Visual Studio (for development) under Windows OS. Even I would be interested in knowing this information for any 3rd party application.

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  • ANTS Memory Profiler 7.0

    - by James Michael Hare
    I had always been a fan of ANTS products (Reflector is absolutely invaluable, and their performance profiler is great as well – very easy to use!), so I was curious to see what the ANTS Memory Profiler could show me. Background While a performance profiler will track how much time is typically spent in each unit of code, a memory profiler gives you much more detail on how and where your memory is being consumed and released in a program. As an example, I’d been working on a data access layer at work to call a market data web service.  This web service would take a list of symbols to quote and would return back the quote data.  To help consolidate the thousands of web requests per second we get and reduce load on the web services, we implemented a 5-second cache of quote data.  Not quite long enough to where customers will typically notice a quote go “stale”, but just long enough to be able to collapse multiple quote requests for the same symbol in a short period of time. A 5-second cache may not sound like much, but it actually pays off by saving us roughly 42% of our web service calls, while still providing relatively up-to-date information.  The question is whether or not the extra memory involved in maintaining the cache was worth it, so I decided to fire up the ANTS Memory Profiler and take a look at memory usage. First Impressions The main thing I’ve always loved about the ANTS tools is their ease of use.  Pretty much everything is right there in front of you in a way that makes it easy for you to find what you need with little digging required.  I’ve worked with other, older profilers before (that shall remain nameless other than to hint it was created by a very large chip maker) where it was a mind boggling experience to figure out how to do simple tasks. Not so with AMP.  The opening dialog is very straightforward.  You can choose from here whether to debug an executable, a web application (either in IIS or from VS’s web development server), windows services, etc. So I chose a .NET Executable and navigated to the build location of my test harness.  Then began profiling. At this point while the application is running, you can see a chart of the memory as it ebbs and wanes with allocations and collections.  At any given point in time, you can take snapshots (to compare states) zoom in, or choose to stop at any time.  Snapshots Taking a snapshot also gives you a breakdown of the managed memory heaps for each generation so you get an idea how many objects are staying around for extended periods of time (as an object lives and survives collections, it gets promoted into higher generations where collection becomes less frequent). Generating a snapshot brings up an analysis view with very handy graphs that show your generation sizes.  Almost all my memory is in Generation 1 in the managed memory component of the first graph, which is good news to me, because Gen 2 collections are much rarer.  I once3 made the mistake once of caching data for 30 minutes and found it didn’t get collected very quick after I released my reference because it had been promoted to Gen 2 – doh! Analysis It looks like (from the second pie chart) that the majority of the allocations were in the string class.  This also is expected for me because the majority of the memory allocated is in the web service responses, so it doesn’t seem the entities I’m adapting to (to prevent being too tightly coupled to the web service proxy classes, which can change easily out from under me) aren’t taking a significant portion of memory. I also appreciate that they have clear summary text in key places such as “No issues with large object heap fragmentation were detected”.  For novice users, this type of summary information can be critical to getting them to use a tool and develop a good working knowledge of it. There is also a handy link at the bottom for “What to look for on the summary” which loads a web page of help on key points to look for. Clicking over to the session overview, it’s easy to compare the samples at each snapshot to see how your memory is growing, shrinking, or staying relatively the same.  Looking at my snapshots, I’m pretty happy with the fact that memory allocation and heap size seems to be fairly stable and in control: Once again, you can check on the large object heap, generation one heap, and generation two heap across each snapshot to spot trends. Back on the analysis tab, we can go to the [Class List] button to get an idea what classes are making up the majority of our memory usage.  As was little surprise to me, System.String was the clear majority of my allocations, though I found it surprising that the System.Reflection.RuntimeMehtodInfo came in second.  I was curious about this, so I selected it and went into the [Instance Categorizer].  This view let me see where these instances to RuntimeMehtodInfo were coming from. So I scrolled back through the graph, and discovered that these were being held by the System.ServiceModel.ChannelFactoryRefCache and I was satisfied this was just an artifact of my WCF proxy. I also like that down at the bottom of the Instance Categorizer it gives you a series of filters and offers to guide you on which filter to use based on the problem you are trying to find.  For example, if I suspected a memory leak, I might try to filter for survivors in growing classes.  This means that for instances of a class that are growing in memory (more are being created than cleaned up), which ones are survivors (not collected) from garbage collection.  This might allow me to drill down and find places where I’m holding onto references by mistake and not freeing them! Finally, if you want to really see all your instances and who is holding onto them (preventing collection), you can go to the “Instance Retention Graph” which creates a graph showing what references are being held in memory and who is holding onto them. Visual Studio Integration Of course, VS has its own profiler built in – and for a free bundled profiler it is quite capable – but AMP gives a much cleaner and easier-to-use experience, and when you install it you also get the option of letting it integrate directly into VS. So once you go back into VS after installation, you’ll notice an ANTS menu which lets you launch the ANTS profiler directly from Visual Studio.   Clicking on one of these options fires up the project in the profiler immediately, allowing you to get right in.  It doesn’t integrate with the Visual Studio windows themselves (like the VS profiler does), but still the plethora of information it provides and the clear and concise manner in which it presents it makes it well worth it. Summary If you like the ANTS series of tools, you shouldn’t be disappointed with the ANTS Memory Profiler.  It was so easy to use that I was able to jump in with very little product knowledge and get the information I was looking it for. I’ve used other profilers before that came with 3-inch thick tomes that you had to read in order to get anywhere with the tool, and this one is not like that at all.  It’s built for your everyday developer to get in and find their problems quickly, and I like that! Tweet Technorati Tags: Influencers,ANTS,Memory,Profiler

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  • Crash on iOS when system purges memory and closes a UIViewController

    - by Amiramix
    My application is crashing when one of the views is purged from memory because of low-memory condition. At least this is what I understand from the crashlog. It happens on numerous screens but only when opening a Facebook dialog (using the Facebook SDK). Basically, looks like the system sometimes runs out of memory when we need to present a Facebook dialog (e.g. to let user post something on the Facebook timeline). Date/Time: 2012-03-14 19:47:33.819 +0000 OS Version: iPhone OS 5.1 (9B176) Report Version: 104 Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x30000008 Crashed Thread: 0 Thread 0 name: Dispatch queue: com.apple.main-thread Thread 0 Crashed: 0 libobjc.A.dylib 0x30f2bf78 objc_msgSend + 16 1 MyApp 0x00003c0e -LTBaseViewController viewDidUnload (LTBaseViewController.m:145) 2 MyApp 0x00004ea2 -LTBaseTableViewController viewDidUnload (LTBaseTableViewController.m:90) 3 UIKit 0x33766bd8 -[UIViewController unloadViewForced:] + 244 4 UIKit 0x338ae492 -[UIViewController purgeMemoryForReason:] + 58 5 Foundation 0x3071a4f8 __57-NSNotificationCenter addObserver:selector:name:object:_block_invoke_0 + 12 6 CoreFoundation 0x30e95540 ___CFXNotificationPost_block_invoke_0 + 64 7 CoreFoundation 0x30e21090 _CFXNotificationPost + 1400 8 Foundation 0x3068e3e4 -NSNotificationCenter postNotificationName:object:userInfo: + 60 9 Foundation 0x3068fc14 -NSNotificationCenter postNotificationName:object: + 24 10 UIKit 0x3387926a -UIApplication _performMemoryWarning + 74 11 UIKit 0x33879364 -UIApplication _receivedMemoryNotification + 168 12 libdispatch.dylib 0x36a12252 _dispatch_source_invoke + 510 13 libdispatch.dylib 0x36a0fb1e _dispatch_queue_invoke$VARIANT$up + 42 14 libdispatch.dylib 0x36a0fe64 _dispatch_main_queue_callback_4CF$VARIANT$up + 152 15 CoreFoundation 0x30e9c2a6 __CFRunLoopRun + 1262 16 CoreFoundation 0x30e1f49e CFRunLoopRunSpecific + 294 17 CoreFoundation 0x30e1f366 CFRunLoopRunInMode + 98 18 GraphicsServices 0x33fb6432 GSEventRunModal + 130 19 UIKit 0x336f5e76 UIApplicationMain + 1074 20 MyApp 0x00004818 main (main.m:16) 21 MyApp 0x000023b4 0x1000 + 5044 I checked and there are almost no memory leaks, e.g. when testing the app for an hour the total memory leaked was around 2-3Kb caused by some string-copying libraries. So I don't believe this is caused by the application. I guess that when the phone is not restarted for some time there are applications running in the background and when using Facebook SDK the memory becomes a problem and the system tries to recover the memory from random applications, including my application. My question is, how can I prevent this crash from happening? How should I handle unloadViewForced on a view controller to make the app more robust in low-memory conditions? And lastly, am I right that this crashlog suggests the crash occurred because the system tried to free memory and my application didn't handle it properly? Any help greatly appreciated.

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  • C++ std::vector memory/allocation

    - by aaa
    from a previous question about vector capacity, http://stackoverflow.com/questions/2663170/stdvector-capacity-after-copying, Mr. Bailey said: In current C++ you are guaranteed that no reallocation occurs after a call to reserve until an insertion would take the size beyond the value of the previous call to reserve. Before a call to reserve, or after a call to reserve when the size is between the value of the previous call to reserve and the capacity the implementation is allowed to reallocate early if it so chooses. So, if I understand correctly, in order to assure that no relocation happens until capacity is exceeded, I must do reserve twice? can you please clarify it? I am using vector as a memory stack like this: std::vector<double> memory; memory.reserve(size); memory.insert(memory.end(), matrix.data().begin(), matrix.data().end()); // smaller than size size_t offset = memory.size(); memory.resize(memory.capacity(), 0); I need to guarantee that relocation does not happen in the above. thank you. ps: I would also like to know if there is a better way to manage memory stack in similar manner other than vector

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  • Minimum percentage of free physical memory that Linux require for optimal performance

    - by csoto
    Recently, we have been getting questions about this percentage of free physical memory that OS require for optimal performance, mainly applicable to physical compute nodes. Under normal conditions you may see that at the nodes without any application running the OS take (for example) between 24 and 25 GB of memory. The Linux system reports the free memory in a different way, and most of those 25gbs (of the example) are available for user processes. IE: Mem: 99191652k total, 23785732k used, 75405920k free, 173320k buffers The MOS Doc Id. 233753.1 - "Analyzing Data Provided by '/proc/meminfo'" - explains it (section 4 - "Final Remarks"): Free Memory and Used Memory Estimating the resource usage, especially the memory consumption of processes is by far more complicated than it looks like at a first glance. The philosophy is an unused resource is a wasted resource.The kernel therefore will use as much RAM as it can to cache information from your local and remote filesystems/disks. This builds up over time as reads and writes are done on the system trying to keep the data stored in RAM as relevant as possible to the processes that have been running on your system. If there is free RAM available, more caching will be performed and thus more memory 'consumed'. However this doesn't really count as resource usage, since this cached memory is available in case some other process needs it. The cache is reclaimed, not at the time of process exit (you might start up another process soon that needs the same data), but upon demand. That said, focusing more specifically on the percentage question, apart from this memory that OS takes, how much should be the minimum free memory that must be available every node so that they operate normally? The answer is: As a rule of thumb 80% memory utilization is a good threshold, anything bigger than that should be investigated and remedied.

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  • How can I free all allocated memory at once?

    - by Tommy
    Here is what I am working with: char* qdat[][NUMTBLCOLS]; char** tdat[]; char* ptr_web_data; // Loop thru each table row of the query result set for(row_index = 0; row_index < number_rows; row_index++) { // Loop thru each column of the query result set and extract the data for(col_index = 0; col_index < number_cols; col_index++) { ptr_web_data = (char*) malloc((strlen(Data) + 1) * sizeof(char)); memcpy (ptr_web_data, column_text, strlen(column_text) + 1); qdat[row_index][web_data_index] = ptr_web_data; } } tdat[row_index] = qdat[col_index]; After the data is used, the memory allocated is released one at a time using free(). for(row_index = 0; row_index < number_rows; row_index++) { // Loop thru all columns used for(col_index = 0; col_index < SARWEBTBLCOLS; col_index++) { // Free memory block pointed to by results set array free(tdat[row_index][col_index]); } } Is there a way to release all the allocated memory at once, for this array? Thank You.

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  • memory issue iPad 4.2 crashes

    - by Manoj Kumar
    I am developing a application which receives 600-700 KB of XML data from the server. I have to do some manipulations in that data so once received the data the memory increases to 600 KB to 2 M.B. Already view occupied 4 M.B of memory in the application. So while processing the XML data i m doing some manipulation(pre-parsing) and the memory increases to 600 K.B to 2 M.B and finally decreases to 600 K.B. due to increase in memory, application gives the memory warning. While getting memory warning i m releasing all the views in the navigation controller but it releases only 1 M.B of memory. Even though I release all the views the application is crashing. Please help me out in this issue. It happens in iPad 4.2. Thanks in advance

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  • Memory address of a variable

    - by dotnetvoyager
    Hi Everyone, Is it possible to get the memory address of a variable in C#. What I am trying to do is very simple. I want to declare variables of type Double, Float, Decimal and assign the value 1.1 to each of these variables. Then I would like to go and see how these values are represented in memory. I need to get the memory address of the variable in order to see how its stored in memory. Once I have the memory address I plan to put a break point in the code and use the Debug - Windows - Memory option in visual studio to see how the numbers are stored in memory. Cheers,

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  • Control SQL Server CLR Reserved Memory

    - by Ryu
    I've recently enabled CLR on my 64 bit SQL Server 2005 machine for usage of about 3 procs. When I run the following query to gather some info on memory usage... select single_pages_kb+ multi_pages_kb + virtual_memory_committed_kb as TotalMemoryUsage, virtual_memory_reserved_kb from sys.dm_os_memory_clerks where type = 'MEMORYCLERK_SQLCLR' I get 129 mb MemoryUsage and 6.3 gb Virtual Memory Reserved The total memory of the machine is 21 gig. What does reserved virtual memory mean exactly and how can I control the size that is allocated? 6 gig is overkill for what we're doing and the memory would be much better utilized by the sproc cache. I'm concerned this reserved memory will cause swapping to the page file. Please help me take back control of the memory! Thanks

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  • Are memory leaks ever ok?

    - by Imbue
    Is it ever acceptable to have a memory leak in your C or C++ application? What if you allocate some memory and use it until the very last line of code in your application (for example, a global object's deconstructor)? As long as the memory consumption doesn't grow over time, is it OK to trust the OS to free your memory for you when your application terminates (on Windows, Mac, and Linux)? Would you even consider this a real memory leak if the memory was being used continuously until it was freed by the OS. What if a third party library forced this situation on you? Would refuse to use that third party library no matter how great it otherwise might be? I only see one practical disadvantage, and that is that these benign leaks will show up with memory leak detection tools as false positives.

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  • CUDA Global Memory, Where is it?

    - by gamerx
    I understand that in CUDA's memory hierachy, we have things like shared memory, texture memory, constant memory, registers and of course the global memory which we allocate using cudaMalloc(). I've been searching through whatever documentations I can find but I have yet to come across any that explicitly explains what is the global memory. I believe that the global memory allocated is on the GDDR of graphics card itself and not the RAM that is shared with the CPU since one of the documentations did state that the pointer cannot be dereferenced by the host side. Am I right?

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  • How to configure ubuntu for lightweight low-memory usage?

    - by augustin
    I just upgraded an old, secondary computer to the latest Kubuntu (10.10). It seems the effort was a bit too much for the hardware and one 512MB memory module died. I tried to take it away, clean the connectors, put it back several times, but to no avail. Until such a time I can find a second hand DDR memory module, I am left with a meagre 256MB RAM, which is below the official requirements (384MB) to run Kubuntu/KDE. Indeed: the computer constantly swaps the memory, making everything painfully slow. Since Kubuntu is already installed and I use it on all my computers (and I want to keep KDE for when I really need it), how can I configure ubuntu to squeeze out every bit of unnecessary memory usage? This is a secondary computer but still very useful. We use it mostly for web browsing. A "lightweight" tag is missing.

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  • How to configure kubuntu for lightweight low-memory usage?

    - by augustin
    I just upgraded an old, secondary computer to the latest Kubuntu (10.10). It seems the effort was a bit too much for the hardware and one 512MB memory module died. I tried to take it away, clean the connectors, put it back several times, but to no avail. Until such a time I can find a second hand DDR memory module, I am left with a meagre 256MB RAM, which is below the official requirements (384MB) to run Kubuntu/KDE. Indeed: the computer constantly swaps the memory, making everything painfully slow. Since Kubuntu is already installed and I use it on all my computers (and I want to keep KDE for when I really need it), how can I configure Kubuntu to squeeze out every bit of unnecessary memory usage? This is a secondary computer but still very useful. We use it mostly for web browsing. A "lightweight" tag is missing.

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  • In C++ Good reasons for NOT using symmetrical memory management (i.e. new and delete)

    - by Jim G
    I try to learn C++ and programming in general. Currently I am studying open source with help of UML. Learning is my hobby and great one too. My understanding of memory allocation in C++ is that it should be symmetrical. A class is responsible for its resources. If memory is allocated using new it should be returned using delete in the same class. It is like in a library you, the class, are responsibility for the books you have borrowed and you return them then you are done. This, in my mind, makes sense. It makes memory management more manageable so to speak. So far so good. The problem is that this is not how it works in the real world. In Qt for instance, you create QtObjects with new and then hand over the ownership of the object to Qt. In other words you create QtObjects and Qt destroys them for you. Thus unsymmetrical memory management. Obviously the people behind Qt must have a good reason for doing this. It must be beneficial in some kind of way, My questions is: What is the problem with Bjarne Stroustrups idea about a symmetrical memory management contained within a class? What do you gain by splitting new and delete so you create an object and destroy it in different classes like you do in Qt. Is it common to split new and delete and why in such case, in other projects not involving Qt? Thanks for any help shedding light on this mystery!

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  • Debug unstable Apache server under Debian

    - by almo
    Since yesterday my Apache server that runs on a Debian machine runs very unstable. Sometiems my websites load and sometimes not. I think it has to do with the memory since my Apache log is full of Out of memory (allocated 262144) (tried to allocate 4480 bytes). I also attached a screenshot of the memory graph. A server restart resolves the problem temporarily. I looked at the processes that are using memory but the biggest one is MySQL with 6.5%. Where else can look for the problem? Edit: I did a free -m right after rebooting and one about 2 hours later. I think the trend is visible: root@xxx:~# free -m total used free shared buffers cached Mem: 4016 731 3284 0 80 200 -/+ buffers/cache: 449 3566 Swap: 459 0 459 root@xxx:~# free -m total used free shared buffers cached Mem: 4016 2466 1550 0 92 473 -/+ buffers/cache: 1900 2115 Swap: 459 0 459

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  • 16 bit processor , memory addressing and memory cells

    - by Zia ur Rahman
    Suppose the accumulater register of the processor is of 16 bit , now we can call this processor as 16 bit processor, that is this processor supports 16 bit addressing. now my question is how we can calculate the number of memory cells that can be addressed by 16 bit addressing? according to my calculation 2 to the power 16 becomes 65055 it means the memory have 65055 cells now if we take 1KB=1000 Bytes then this becomes 65055/1000=65.055 now this means that 65 kilo bytes memory can be used with the processor having 16 bit addressing. now if we take 1KB=1024 Bytes then this becomes 65055/1024=63.5 ,it means that 63 kilo bytes memory can be used with this processor, but people say that 64 kilo bytes memory can be used. Now tell me am i right or wrong and why i am wrong why people say that 64kb memory can be used with the processor having 16 bit addressing?

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  • T-Mobile G1 (MSM7200) GPU Memory

    - by Reflog
    Hello. I'm trying to find some information regarding the available GPU (for OpenGL) memory on the T-Mobile G1. This phone has a MSM7200 Qualcomm chip inside with ATI Imageon GPU. Unfortunately I am not able to dig any info regarding the specifics of GPU memory usage. How much memory is available in total for the textures? Is the memory shared with the CPU memory? Thanks in advance, Eli

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