It is an extension of memory address space which is logically appended to the physical memory of a computer by the Memory Management Unit (MMU) of its processor. It is normally realized in operating systems by utilizing free disk space to implement such memory extension and may also be referred to ...

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2
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2answers
96 views

Linux virtual memory tuning to workaround disk I/O issue

I am having a problem with a Linux server that it is writing to much to disk, thus I am having a slow response time due to a big IO wait. I already check smart values for the disks and are OK. This is ...
1
vote
0answers
46 views

Why is my server using swap even though there is lots of RAM available? [duplicate]

My server has 24 cores, 16 GB RAM, and 8 SSDs on raid 0 (I think). I've noticed it is now using a low of swap space, even though there is plenty of RAM available. load average: 2.70, 2.54, 2.50 Mem: ...
0
votes
3answers
70 views

Load balancing for a running server process with sessions

I'm developing a server application that accepts incoming connections and works with client applications. The customer wants to have two machines working: in case one goes offline, the second will ...
0
votes
1answer
72 views

Can high disk cache usage lead to external fragmentation and ultimately to page allocation failures?

We're getting page allocation failures on a Linux server (3.2 kernel). We've been told the problem is directly related to the high use of the memory for cache; this would lead to external ...
0
votes
0answers
97 views

What is using all of my memory on Ubuntu 12.04?

I keep getting alarms from Rackspace telling me that my memory usage is too high, but I can't seem to find the culprit. I ran top SHIFT + M to see top output sorted by memory, and this is what I get ...
0
votes
1answer
2k views

What is nonpaged pool?

I have a Server 2008 R2 that I maintain on a day-to-day basis. The server is good and operating fine but it keeps sending me event 2019 error logs. "The server was unable to allocate from the system ...
0
votes
0answers
45 views

Why would Memory\Available Bytes go down, even when Virtual Memory used is constant?

I have a long-running application that continually loops through video files. It runs for some hours, and then a message box appears along the lines of "The system is running low on memory...". I've ...
0
votes
1answer
135 views

MongoDB: big size of mapped memory

I'm not expert in mongo memory management but some things confuse me. I use Mongo 2.4.9 and I have a replica sets for three nodes. I have performed db.serverStatus().mem and see that size of mapped is ...
3
votes
2answers
206 views

How can I keep important VMs in memory without disabling swap?

VM Host -> Xenon E5-2440 w/ 48G mem... Everything runs CentOS6.5 (2.6.32-431) I have 4 guest VMs running each w/ 2G of memory. Their disk images are local files. The host machine is also running a ...
3
votes
3answers
408 views

High Memory 64bit server, not using all ram

I have several high memory linux servers running centos 64bit, and after 10-20 days of uptime I have noticed on all of these servers they dont actually use all the ram available to then (they all have ...
1
vote
0answers
42 views

Stack , data and address space limits on an Ubuntu server

I am running an Ubuntu server which has around 5000 users. The users are allowed to SSH in to the system. So in order to cap the memory used up by a process I have capped the address space limits ...
1
vote
1answer
1k views

Large virtual memory size of ElasticSearch JVM

I am running a JVM to support ElasticSearch. I am still working on sizing and tuning, so I left the JVM's max heap size at ElasticSearch's default of 1GB. After putting data in the database, I find ...
0
votes
1answer
1k views

Running out of memory, or running out of disk space?

I'm running a database loading process (osm2pgsql) which is failing: Processing: Node(17404k 148.8k/s) Way(1351k 6.38k/s) Relation(9520 29.94/s)way_done failed: ERROR: could not extend file ...
1
vote
1answer
55 views

Virtual memory and CPU usage catch 20/20?

I am looking at this system below with ensuring we have enough memory to carry out day to day tasks, we have been hitting a bottleneck recently because there was only a 2GB page file, I've changed ...
1
vote
1answer
158 views

SQL Server Page File On 3TB San Drive

We have a Windows Server 2008 R2 box with 288GB of RAM. The system has created a page file about about the same size. This is expected, however, when I try to move the file to a SAN drive that is ...
2
votes
1answer
60 views

What is System Code Total Bytes

I am trying to use perfmon, and according to MSDN, the "System Code Total Bytes" counter ... Shows the size, in bytes, of pageable operating system code currently in virtual memory. It is a ...
0
votes
2answers
129 views

how to access physical memory in BSD platform from terminal or using any system call ?

i just not know how to use mem command in BSD to access physical memory or virtual memory to get the ACPI tables and their Address ....... $mem Enter mem command not found .... so what can i do ? ...
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votes
1answer
161 views

How is the Total Virtual Memory Calculated in this server? [closed]

From the images below, I am not sure how the 'Total Virtual Memory' available is shown as 7.82 GB in the system information (winmsd.exe) ? I always though it is nothing but the page file size ...
0
votes
1answer
59 views

Windows Pagefile placement

Is it possible to reserve a desired region of a given hard disk drive for placement of the pagefile.sys before enabling the page file on that drive?
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votes
4answers
524 views

What is the *optimal* virtual memory configuration for this server? [closed]

I am maintaining a Small Business Server 2003 (x86) server, that was originally installed and configured by someone else in early 2009. Recently, although we have never had any obvious memory-related ...
1
vote
2answers
3k views

How do I find the root cause of Memory pressure failure on an SQL server 2008?

One of the servers I have been performance monitoring started throwing the following warnings from the Resource-Exhaustion-Detector: Windows successfully diagnosed a low virtual memory condition. ...
1
vote
1answer
473 views

Proxmox - Assign more memory to KVM VM

Is it possible to assign more memory to a KVM virtual machine without restarting it? I changed the memory size of a VM using the Proxmox web interface, but can't see that increase in the guest.
5
votes
2answers
324 views

Automatically suspend/hibernate a process when too much memory taken

I'm running a small Debian compute cluster on 8-core PCs with 16GB of RAM. I'm running batches of about 1k tasks (each batch has a total expected time of a month to be finished). A single task is ...
1
vote
2answers
89 views

Impact on various Linux commands on a Varnish server

I know Varnish use memory mapped technique for caching data in memory, what if I execute the following commands on a machine, are there any penalty on the overall Varnish's performance? e.g. Total ...
-1
votes
3answers
875 views

Is this server using too much RAM or virtual memory ? (screen attached) [closed]

I have a VPS with 512MB of ram 40GB storage 1CPU, I run a small domain parking service on it. It is on CentOS, MySQL, Apache, etc. Now my hosting provider claims that my server is putting too much ...
3
votes
3answers
87 views

Virtual Server Memory not a power/multiple of 2

In the old times (before virtualization), memory came in powers/multiples of 2, because that is the way memory is manufactured. Nowadays that we create virtual servers that don't have real physical ...
2
votes
1answer
2k views

How to tune system settings for mongoDB on Linux?

Trying to squeeze a lot out of one question here -- please bear with me. Although the MongoDB man pages make several useful recommendations about system settings like ulimit ...
1
vote
1answer
185 views

Using Linux /proc/meminfo to avoid overloading server via swapping

I am trying to find a metric to use that will tell me if starting another process estimated to use N bytes of memory will have an adverse impact on system performance. I know that the /proc/meminfo ...
2
votes
1answer
1k views

Is it bad if your Virtual Bytes count is high in an application pool in IIS?

Related to What does Virtual Bytes mean in Worker Processes pane in IIS7.5 Manager? I have a server running a few different sites. We're seeing some performance and memory issues. When I go to ...
0
votes
2answers
716 views

virtual memory optimization on exchange server 2010

Hi I did some Google searching but came up blank I know mycomputer/computer > Properties > advance System settings > Advance[tab] > Settings[Performance] > Advance [Tab] > Change > customsige ...
1
vote
1answer
940 views

How to find out who used all RAM (UPDATED)?

Sometimes I find that 100% of my small Debian machine's RAM is used, but I can't figure out how to find this leak: top show that all memory is used, but I can't find any process that consumed this ...
1
vote
1answer
2k views

How much space is in a Solaris /tmp filesystem?

On Solaris, the /tmp filesystem is a filesystem of type "tmpfs". It's implemented in the kernel by allocated space from the virtual memory pool. That means allocation interacts with the available RAM ...
1
vote
1answer
318 views

CentOS webserver memory overflow - cannot log in

Few days ago, my CentOS 6.2 webserver with ISPconfig 3 went down to the extent I wan't able to log in via SSH nor using a console. The console was full of messages "out of memory, killing process, ...
2
votes
1answer
100 views

How to interpret increasing SHR reported by top?

The man page for top defines SHR as: t: SHR -- Shared Mem size (kb) The amount of shared memory used by a task. It simply reflects memory that could be potentially shared with other ...
1
vote
2answers
827 views

Linux out of memory on VPS

On my VPS (CentOS) 4GB ram (2 + 2 dynamically assigned when needed) and i have tomcat running with following options JAVA_OPTS="-Xms256m -Xmx2048m -XX:MaxPermSize=256m". Now when i try to start ...
1
vote
1answer
349 views

100GB Virtual Memory on 64GB server without swap [duplicate]

Possible Duplicate: Understanding virtual memory usage > swap + physical on Linux We have the following process: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND ...
1
vote
2answers
783 views

Where's the Swap File/Partition?

I'm investigating the virtual memory configuration of a Debian based Amazon EC2 instance, and as my background isn't in system admin, I'm slightly confused by what I'm seeing. We're using MongoDB, ...
1
vote
0answers
89 views

Getting the virtual memory address for (major) page faults

On a Linux (Cent OS 5) system, I have a process that accesses a large amount of memory mapped files. The process is generating a large amount of page faults because the aggregated size of the mapped ...
0
votes
4answers
263 views

Fast small static file serving on a VPS - avoiding the Disk

I need to serve a large number of very small static files (e.g. 1Million, ~1KB), from a VPS. My current favoured approach is Nginx, but my main concern is hitting slow VPS disks. Is there an ...
2
votes
0answers
144 views

virtual memory commited

After a server bounce happens, and after around 40-45 days time period, we receive continuous “Committed Virtual Memory” alerts which indicates the usage of swap space in the magnitude of >4GB This ...
4
votes
1answer
498 views

How do you measure the memory footprint of a set of forked processes?

Say I've got a process using 200MB of memory, and it fork()s: python -c "import os; data='x'*200000000; os.fork(); raw_input()" Programs like 'top' will show each process using 200MB, with very ...
3
votes
0answers
44 views

How can I measure disk cache churn on Linux? [duplicate]

Possible Duplicate: Is there a way to get Cache Hit/Miss ratios for block devices in Linux? I have a file server which serves out large (25GB-1TB+) files over the network from local ...
0
votes
1answer
74 views

Windows Memory being freed before limit is hit during a load test

I'm running a load test on a .NET web application over a LAN. The server hosting the web app is a VM, Windows Server 2008 R2, with 2 GB of RAM and a 3GB limit for virtual memory. No other web ...
6
votes
2answers
1k views

Memory overcommitment on VMware ESXi 5.0

I would like to understand better the possibilities of VmWare ESXi memory overcommitment. I've read this paper from VmWare, so I am familiar with general concepts, such as hypervisor swapping, memory ...
9
votes
1answer
361 views

Ballooning occuring on SQL server

From what I understand ballooning should occur only when the host begins to run out of physical memory, somewhere above 90% usage. I have an SQL server running in a three node cluster (64 GB RAM in ...
1
vote
1answer
2k views

Mysql using high VIRT memory and RES is compartively

is there a way to reduce the VIRT mem usage? I am not sure what the reason is for such high usage. It has reached upto 12g as well. Using top command Tasks: 348 total, 1 running, 344 sleeping, 0 ...
3
votes
1answer
624 views

What is shrink_slab, and why is it showing up in /var/log/messages?

I'm investigating some application issues on a Linux system and noticed this around the time of the most recent problem, but not close enough to be definitively related: Jun 7 17:51:49 localhost ...
-2
votes
1answer
115 views

Is there a way to manually provide virtual memory?

Virtual memory is disabled by the hoster in one of the Windows VServers I use to avoid heavy disk access. At the same time, the RAM provided is only 1GB, which is insufficient for an application I'm ...
3
votes
2answers
4k views

How to sort top result on virtual memory on Redhat Linux?

There is an interactive key "M" to sort by memory, which seems to be sorting on resident memory. Is there a way to sort on virtual memory? I happen to be working on Redhat Linux, but the question is ...
7
votes
4answers
5k views

Understanding virtual memory usage > swap + physical on Linux

I have a process that is reporting in 'top' that it has 6GB of resident memory and 70GB of virtual memory allocated. The strange thing is that this particular server only has 8GB physical and 35GB of ...