Questions tagged [cache]
cache is a component that stores data so future requests for that data can be served faster; the data stored in a cache might be the results of an earlier computation, or the duplicates of data stored elsewhere.
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DNS resolution with reverse proxy connection after server migration
I got a small setup with two private servers ps1 and ps2 at home behind a NAT. One server s1 with public domain s1.com is a small rented vps where I set up as reverse proxy with caddy.
On ps1 I had a ...
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Spin down HDD on Server
I'm running Debian 13 (fresh install) and want to use specifically Nextcloud and Immich on docker on an SSD and 2 HDDs with 10TB for data (and the second for raid/snapraid or backups or similar).
For ...
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When suspending to disk, does memory cache got dumped to disk?
My system has 64GiB of memory. I noticed it usually uses about 20GiB for cache. I wonder if I do "suspend to disk", does the cached part get dumped to disk as well, or is it written to disk ...
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Is it a good idea to have inode size of 2048 bytes + inline_data on an ext4 filesystem?
I only recently "discovered" the inline_data feature of ext4, although it seems to have been around for 10+ years.
I ran a few statistics on various of my systems (desktop/notebook + server),...
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How to get the stats of an lvm cache?
I am using an lvm cache in the most usual combination (small, fast ssd before a huge, slow hdd). It is simply awesome.
However, I have not found a way to know, how many blocks are actually cached and ...
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Why does the program that reads files still run very fast after clearing the page cache?
Test environment: Virtual Machine(Windows 11, VMware Workstation Pro), Ubuntu 22.04, mechanical hard drive.
Use the following command to generate 1GB of test data:
dd if=/dev/urandom of=test.data ...
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fork() Causes DMA Buffer in Physical Memory to Retain Stale Data on Subsequent Writes
I'm working on a C++ application on Ubuntu 20.04 that uses PCIe DMA to transfer data from a user-space buffer to hardware. The buffer is mapped to a fixed 1K physical memory region via a custom ...
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How to prioritize SSD page cache eviction over HDD with slower speed?
I have a large slow HDD and a small fast SSD. This is about reads not RAID. My desktop grinds to a near-halt when switching back to Firefox or man pages after (re/un)-loading 12+ GiB of Linux kernel ...
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What is the difference and relation between the "--default-cache-ttl" and "--max-cache-ttl" options?
About GPG is mentioned the gpg-agent and I read the following answer:
gpg does not ask for password
Where is mentioned the --default-cache-ttl and --max-cache-ttl options. So I found this official ...
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Alternate way to get the CPU cache size
I have a project where I need to get the size of the cache on my Linux machine. I don't know the linux distro, and the /etc/os-release file does not exist.
I only know the kernel and architecture:
...
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Synology SSD cache size requirement
I've been running a new Synology RS3621RPxs for several weeks, and my 4TB SSD cache shows:
Cache composition: Reusable (341 GB) / Total (3.6 TB)
If I'm reading that correctly, my nas isn't even using ...
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Share one SSD Cache across multiple volumes & storage pools on Synology NAS
I have a new Synology NAS with 2 storage pools, and I have one volume per pool.
I have added a single SSD to the NAS to serve as a cache, and was able to add it to the first storage pool. This is a ...
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Does linux have a cache for standard output?
I know that recently accessed files are cached into the RAM, but is there a cache for frequent commands?
For example, if I run cat file.txt multiple time, file.txt will be cached after the first ...
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Is there a FUSE-based caching solution for selective prefetching from a remote filesystem?
I am working with a remote parallel file system (CephFS), mounted at /mnt/mycephfs/, which contains a large dataset of small files (200 GB+). My application trains on these files, but reading directly ...
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SSL certa sha changed, but Chrome still uses old one
I was forced to change ssl certificate for one from my domains. So, cert changed, sha256 changed. Old cert was not expired yet, but it's now replaced with new one.
But, it looks like Chrome does not ...
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