Unix and Linux Stack Exchange
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Questions tagged [ram]

Random Access Memory is a fast and volatile data-storage bank used in computers to store data and machine code currently being used.

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How do you empty the buffers and cache on a Linux system?

Prior to doing some benchmarking work how would one free up the memory (RAM) that the Linux Kernel is consuming for its buffers and cache? Note that this is mostly useful for benchmarking. Emptying the buffers and cache reduces performance! If…
slm
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How much RAM does the kernel use?

This question is motivated by my shock when I discovered that Mac OS X kernel uses 750MB of RAM. I have been using Linux for 20 years, and I always "knew" that the kernel RAM usage is dwarfed by X (is it true? has it ever been true?). So, after some…
sds
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Loading of shared libraries and RAM usage

I'm wondering about the way Linux manages shared libraries. (actually I'm talking about Maemo Fremantle, a Debian-based distro released in 2009 running on 256MB RAM). Let's assume we have two executables linking to libQtCore.so.4 and using its…
marmistrz
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Unix command to tell how much RAM was used during program runtime?

Let's say I'm running a script (e.g. in Python). In order to find out how long the program took, one would run time python script1.py Is there a command which keeps track of how much RAM was used as the script was running? In order to find how much…
ShanZhengYang
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How can I fake the amount of installed RAM for a specific program in Linux?

I'm running BOINC on my old netbook, which only has 2 GB of RAM onboard, which isn't enough for some tasks to run. As in, they refuse to, seeing how low on RAM the device is. I have zRAM with backing_dev and zstd algorithm enabled, so in reality,…
Роман Мавроян
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detect number of RAM channels

I'm trying to determine (without physically having access to a machine) the number of RAM channels it supports (single, dual, etc) - AND whether it is configured to use that setup, e.g with four slots and dual channel RAM, you only get dual channel…
Zack Newsham
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How to blacklist a correct bad RAM sector according to MemTest86+ error indication?

MemTest86+ (the version included with Ubuntu 13.04) says Failing address: 002f796c48 - 759.5 MB What should I specify in the memmap kernel parameter to bypass this area? I've tried running memtester 770MB and it says everything is ok so it…
Ivan
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Move /tmp to RAM

I am trying to move /tmp to RAM and obey good practice: /var/tmp should NOT be placed in tmpfs, as it must survive reboots not mount /tmp as a stand-alone tmpfs, but rely on /dev/shm or /run/shm However, things have changed between 2.6 and 3.2…
Massimo
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Is there any way to know the size of L1, L2, L3 cache and RAM in Linux?

Is there any way to know the size of L1, L2, L3 caches and RAM in Linux?
user3692521
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How to tell whether RAM ECC is working?

I'm planning on getting some ECC RAM to replace the non-ECC RAM I currently have installed on my Asus M5A97 Pro motherboard (AMD 970 chipset, FX-6100 CPU). After I install the RAM, how do I tell whether the ECC feature of the RAM is working…
user
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How to view RAM's SPD / timings table?

In Linux Mint, how to get the same information presented in the lower half of the below picture? Output by CPU-Z in Windows: What I've tried: Running CPU-Z 1.66 in Wine as Windows 95, 98 and XP. CPU-G i-nex sudo lshw sudo dmidecode decode-dimms
gom
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How to find information about my RAM?

Possible Duplicate: Can I identify my RAM without shutting down linux? I'd like to know the type, size, and model. But I'd like to avoid having to shut down and open the machine.
Zignd
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How can I see memory usage history?

I am familiar with several commands like top, htop, free, etc. However, is there a command to see the peak/burst memory usage of the entire server (not individual processes) over, say, the last 30 days/24 hours/etc.?
Michael Yaeger
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Can Linux "run out of RAM"?

I saw several posts around the web of people apparently complaining about a hosted VPS unexpectedly killing processes because they used too much RAM. How is this possible? I thought all modern OS' provide "infinite RAM" by just using disk swap for…
themirror
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What is the meaning of `shared` memory in the `free` command?

The fourth column in the output of free is named shared. On most outputs I can see in internet, the shared memory is zero. But that's not the case on my computer: $ free -h total used free shared buff/cache …
BertS
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