Synonym for: RAM - Acronym for: Random Access Memory, a type of computer data storage.
157
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14answers
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Any benefit or detriment from removing a pagefile on an 8GB RAM machine?
I'm running Windows 7 on a dual core, x64 AMD with 8GB RAM.
Do I even need a pagefile?
Will removing it help or hurt performance?
Would it make a difference if this is a server or a desktop?
Does ...
32
votes
7answers
2k views
Database server: Small quick RAM or large slow RAM?
We are currently designing our new database servers, and have come up with a trade off I'm not entirely sure of how to answer.
These are our options: 48GB 1333MHz, or 96GB 1066MHz.
My thinking is ...
29
votes
3answers
25k views
Meaning of the buffers/cache line in the output of free
Why does my server show
total used free shared buffers cached
Mem: 12286456 11715372 571084 0 81912 6545228
-/+ buffers/cache: 5088232 7198224
...
29
votes
3answers
14k views
In Linux, what is the difference between “buffers” and “cache” reported by the free command?
This is an old question that I've seen from time to time. My understanding of it is rather limited (having read about the differences a long time ago, but the factoid(s) involved never really stuck).
...
25
votes
8answers
6k views
Linux: how to explicitly unswap everything possible?
I've launched something that took lots of memory and now everything lags a lot.
I guess all applications' memory has gone to swap in order to free some space for the memory-intensive process, and now ...
24
votes
9answers
4k views
To improve SQL performance, why not just put lots of RAM rather than having faster hard disks?
People keep telling me that in order to improve an SQL server's performance, buy the fastest hard disks possible with RAID 5, etc.
So I was thinking, instead of spending all the money for ...
20
votes
4answers
1k views
Can MySQL effectively take advantage of 64 GB RAM?
We have been running into a problem where querying a table that has approximately 50 million rows, and has an index size of 4 GB (table size of about 6 GB) results in the database server swapping ...
20
votes
8answers
18k views
How to reduce memory usage on a Unix webserver
I'm currently using a Joyent Accelerator to host my webapps, and it's working fine, however I need to reduce costs so I'm downgrading my current plan and that imposes some new memory limits (256M rss, ...
19
votes
5answers
8k views
How to understand the memory usage and load average in linux server
I am using a linux server which has 128GB of memory and 24 cores. I use top to see how much it is used. Its output is pasted at the end of the post. Here are two questions:
(1) I see that each of the ...
18
votes
3answers
12k views
Turn off the Linux OOM killer by default?
The OOM killer on Linux wreaks havoc with various applications every so often, and it appears that not much is really done on the kernel development side to improve this. Would it not be better, as a ...
16
votes
4answers
13k views
What is ECC ram and why is it better?
I've seen a dicussion about ECC ram use on servers. Why is it better?
16
votes
8answers
47k views
Should you disable page file with SSD?
I've been reading this question, and it has a lot of great information.
But assuming you have more than enough ram, I think page file should be disabled on SSD to extend the life time. I know you ...
13
votes
10answers
12k views
Memory usage per user in Linux?
Let's say i have 20 users logged on my linux box. How can I know how much memory each of them is using?
13
votes
4answers
3k views
Mirrored Mode RAM: Is it worth it?
Not really familiar with Intel's "Mirrored Channel Mode" for a Blade Server setup (your typical moderately-heavy MySQL OLTP database running on the bare metal blade; no virtualization right now).
...
13
votes
4answers
9k views
How can I determine the cause of an apparent memory leak in my Apache/PHP based web app?
About once a week, but sometimes even a couple of times a day after running fine for days, my EC2 instances become unresponsive. Munin's memory graphs tell a pretty straightforward story: memory ...
12
votes
3answers
717 views
Balancing RAM when using multiple CPUs
We have HP DL360 G7 server with one cpu and 16G 12G ram. We plan to add another cpu. So, we need also ram for second cpu. Is there any negative performance impact if we add different size of ram to ...
12
votes
13answers
7k views
Simple tool to graph memory usage?
Is there a script that will show memory usage as a graph, for example as a pie-chart, with each process being being a separate slice?
I'm not looking for something like Munin to graph memory usage ...
12
votes
7answers
1k views
How do I inventory the type and speed of a remote computer?
I'm on a Windows 2003/2008 corporate network with 100 users. I've been tasked with increasing the RAM on all end-user workstations.
The problem is we have a mixture of different computers in our ...
12
votes
1answer
3k views
deleting linux cached ram
I have a webserver that has 8GB of ram and is running a pretty intensive php site (1 site) that does file manipulation, graphing, emailing, forums, you name it. The environment is far from static ...
12
votes
6answers
6k views
After upgrading to 2008 R2 Enterprise and installing more RAM, Windows can only see 4.00 GB
(I have also posted this on technet but I'm running out of ideas)
I've upgraded from Windows Server 2008 R2 Standard to Enterprise in order to make use of more RAM. The server previously had 32GB of ...
11
votes
7answers
3k views
SQL Server - Force DB in memory?
We have a beefy Windows 2008 x64 server (4 x 4 core CPU, 32GB RAM) running SQL Server 2005 64-bit. We have a small (6GB) but very important database that is somewhat slow to access until the pages are ...
11
votes
2answers
6k views
Find out which database in SQL Server 2005 uses how much RAM
A friend of mine asked me today (trying to calm down an agitated customer of his) how you could find out in SQL Server 2005 which database uses how much memory (in the server's RAM that is) at any ...
11
votes
5answers
901 views
Linux with 256GB of mem / 48 Cores - Machine starts thrashing/choking with tons of memory left
Machine: Dell r815, CentOS 5.4, 256GB of RAM, 4 x 12 Cores.
We have an application that has a 275GB file. It does an in place sort on 20GB of data at a time i.e. it swaps bits around and replaces ...
11
votes
4answers
39k views
DIMMs: Single vs. Double vs. Quad Rank
What difference does the 'Rank' of DIMMs make to server memory? For example, when looking at server configurations I see the following being offered for the same server:
2GB (1x2GB) Single Rank ...
11
votes
4answers
9k views
SQL Server 2005: There is insufficient system memory to run this query
One of our SQL Servers, which has been running stable for quite some time (years), has recently been throwing insufficient memory errors. From the Application Event Log, we see:
Event ID: 701
...
11
votes
3answers
5k views
Windows Server 2008 R2 Metafile RAM Usage
I have a server which runs Windows Server 2008 R2 x64 with 4GB of RAM which hosts around 2-3 million files, the majority of which are image files.
Over a course of a week, I have noticed that ...
11
votes
3answers
985 views
Can you determine which Apache modules have been used and can be removed?
I, like many people, have a relatively out-of-the-box Apache installation with a lot of default "LoadModule" lines.
Since the beginning, I've installed a lot of software, and to be honest, I don't ...
11
votes
3answers
781 views
96 GB RAM on a Dell T7500 showing up as 78GB in Ubuntu Server 11.04
Running Ubuntu Server 11.04. I've got a new Dell Precision T7500 workstation loaded up with 12x8GB DIMMs and the BIOS shows 96GB but checking /proc/meminfo gives:
cat /proc/meminfo | grep MemTotal
...
10
votes
4answers
4k views
Is it better to have more small ram chips or fewer large ones?
I am currently building a new server. I have options between say
32GB Memory for 2 CPUs, DDR3, 1066MHz (8x4GB Dual Ranked RDIMMs)
and
36GB Memory for 2 CPUs, DDR3, 1066MHz (18x2GB Dual Ranked ...
10
votes
3answers
4k views
Virtual Machine memory usage not appearing in TaskManager
There's something about Windows memory management and it's relationship to TaskManager that I don't understand and I'm hoping someone can enlighten me.
If I'm running a virtual machine (doesn't ...
10
votes
5answers
20k views
How do I get SQL Server to release its memory?
I know SQL likes RAM, but releases it when Windows asks. I know this is how SQL is supposed to work. But I have a Windows Administrator who isn't convinced that SQL will actually return the RAM, and ...
10
votes
2answers
461 views
How do you estimate how much memory to buy?
I have a custom server application that runs on Windows 2008 R2. It is a home grown Windows Service written in .Net supporting a number of custom terminals. I have a test machine that has a similar ...
10
votes
5answers
5k views
How to minimise SpamAssassin (spamd) memory use
I'm using SpamAssassin on Debian (the default configuration with Pyzor, AWL and Bayes disabled, and sa-compile enabled), and each of the spamd child processes consume around 100 to 150MB of memory ...
9
votes
6answers
9k views
Reclaiming memory from SQL Server
I have an SQL Server instance who's memory usage gradually grows until windows will give it no more. It seems logical that the occasional big query result would cause the instance to grow.
Is there a ...
9
votes
8answers
486 views
More RAM vs. more servers
I was recently asked "Do you know when to decide between going for more RAM or more servers?" (in the context of scaling data mining applications).
I had no idea, so what are some ways to decide? I ...
9
votes
4answers
3k views
Eliminating the Page File
I've seen discussions go back and forth on this on several sites, so maybe we can come up with something definitive here.
I have 8 GB memory on my Vista x64 workstation. Do I need a page file (that ...
9
votes
6answers
24k views
Weird memory usage in Windows Server 2008 R2
I hope someone can help. We've got a Windows Server 2008 R2 machine with 16GB of RAM that keeps getting all its available memory eaten by something. Nothing in Task Manager or Resource Monitor reveals ...
8
votes
9answers
4k views
Freeing up memory (RAM) on Ubuntu 8.04 Server
I run an Ubuntu 8.04 on a Slicehost virtual server with some lightweight server apps - apache22, svnserve, mysql, and proftpd. The only serious service limitation is RAM - 256MB is what I'm paying ...
8
votes
7answers
3k views
Would you use ECC RAM in a workstation?
Is ECC RAM recommended for use in workstations, or is it something that only gets used in servers? If non-ECC RAM works in PCs, why would we need ECC RAM at all?
8
votes
7answers
20k views
How to find memory usage of individual Windows services?
Task Manager shows the overall memory usage of svchost.exe. Is there a way to view the memory usage of individual services?
Note this is similar to ...
8
votes
5answers
25k views
Top - what does Virtual memory size mean? …linux/ubuntu
I am running Top to monitor my server performance and 2 of my java processes show virtual memory of upto 800MB-1GB. Is that a bad thing?
What does virtual memory mean? And oh btw, I have swap of 1GB ...
8
votes
7answers
625 views
Statistics on RAM malfunction
Does anyone know about any statistics or studies about how often computers have malfunctioning RAM?
Update: My computer is fine! I don't have RAM problems, I'm interested in the statistics. I get bug ...
8
votes
2answers
3k views
Linux: memory is free but swap is used. Why?
Here are Munin's diagrams.
Memory usage:
http://koryagin.com/w/q/memory-day.png
Swap in/out:
http://koryagin.com/w/q/swap-day.png
Why does Linux decide to increase cache and use swap when the RAM ...
8
votes
1answer
4k views
How to interpret output from Linux 'top' command?
Following a discussion made HERE about how PHP-FPM consuming memory, I just found a problem in reading the memory in top command. Here is a screenshot of my top just after restarting PHP-FPM. ...
8
votes
7answers
12k views
Does DDR3-800 RAM even exist?
I purchased 4 Intel Xeon E5506 processors and a couple of SuperMicro barebones servers from Newegg. Based on everything I saw on Newegg, I thought that I could purchase 1333 Mhz DDR3 RAM.
I was ...
8
votes
4answers
2k views
JVM Memory Consumption
I am trying to run tomcat on a low memory system (150-256Mb). Even though I start the JVM with -Xmx64m (which should be the default anyway), the process immediately takes up 200Mb+.
I wonder why the ...
8
votes
1answer
4k views
Memory Usage Numbers In top/htop
Can someone please explain this top output. Each PHP process is using 30% of the total memory or of the used memory? Furthermore how can it be that the combined used memory across all the PHP ...
8
votes
3answers
7k views
page allocation failure - am I running out of memory?
Lately I've noticing entries like this one in the kern.log of one of my servers:
Feb 16 00:24:05 aramis kernel: swapper: page allocation failure. order:0, mode:0x20
This is what I'd like to know:
...
7
votes
11answers
7k views
Linux server is only using 60% of memory, then swapping
I've got a Linux server that's running our bacula backup system. The machine is grinding like mad because it's going heavy in to swap. The problem is, it's only using 60% of its physical memory!
...
7
votes
5answers
8k views
32-bit Windows Server address > 4GB RAM - How?
This is news to me. I was always under the impression that 32-bit OS could only address 2^32 i.e. 4GB of RAM. Period.
But what's this - ...
