Questions tagged [bcache]

Bcache is a Linux block layer cache that uses SSDs to cache other block devices.

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Many "UBSAN: array-index-out-of-bounds" about bcache at boot time (kernel 6.5.0)

I installed a btrfs filesystem relying on two devices (for btrfs raid1) that are mappers (cryptsetup luksOpen) of bcache devices (NVME + HDD). This btrfs filesystem seems to work perfectly. However, ...
Fade's user avatar
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1 vote
1 answer
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How to recover data from drives in bcache configuration

I'm trying to recover the data in hard drives that was set up in raid and bcache. I'm using ubuntu 22.04 and just migrate the two hard drives in raid 1 to another computer. I have no longer the ssd ...
mariano torres manno's user avatar
1 vote
1 answer
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How can I install Ubuntu 22.04 on a system with an SSD and a hard drive using full disk encryption?

I would like to install Ubuntu 22.04 on a PC with an NVMe solid-state drive for the OS and a traditional hard drive for /home, using full disk encryption. Before I buy the hardware, I have been trying ...
Steve F's user avatar
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Repair grub boot settings to work with bcache on a Terra PC by Wortmann AG

I wanted to try bcache, since I have a large HDD and a smaller SSD. I followed these instructions pretty closely: https://kloppenborg.net/blog/installing-ubuntu-20-04-with-bcache/ Hardware is a Terra ...
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2 votes
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I lost my data on bcache after setting the mode to writethrough

This is my first attempt to ask a question on StackExchange so please expect a not so well organized question. I had 1 512G SSD and 1 4T HDD set up with bcache on Ubuntu 20.4 to be used for nextcloud ...
Jimmy Wu's user avatar
2 votes
0 answers
198 views

How to fix a bcache partition where the pyhsical size is less than the superblock size

I'm in the process of migrating data to a bcache partition. I've created the backing disk and cache disk, and I used dd to copy data from another partition (of the same size) to the new /dev/bcache0 ...
Jonathan Holvey's user avatar
1 vote
2 answers
279 views

Advice using SSD/HDD [closed]

I have 120 GB SSD and 2TB HDD. Now I just wondering how to get best performance. 1st option is to install system on SSD and home to HDD. I have that in my laptop and works nice. But it take only 10% ...
eSlavko's user avatar
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Ubuntu Server 20.04 install custom partitioning

Back when using OpenSUSE for my server, I devised a partitioning scheme that I was very satisfied with - a BTRFS RAID10 on bcache devices. I wanted to recreate this with Ubuntu Server 20.04, but so ...
keraldi's user avatar
1 vote
1 answer
975 views

Can I change my Bcache settings on the fly?

I made a fresh install of ubuntu 20.04 on my desktop, and then, from within the installation, created a bcache device to put my /home sudo make-bcache -C /dev/sdb4 -B /dev/sda1 Where /dev/sdb is the ...
metichi's user avatar
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Bcache seems to need update-initramfs

I'm setting up bcache on ubuntu 20.04. Booting from install CD, I created a bcache dirve by: #modprobe bcache #make-bcache -B /dev/mapper-vgubuntu-root #make-bcache -C /dev/sdb Just after that #...
hakanekat's user avatar
3 votes
0 answers
722 views

Fstrim ruins bcache's performance

Since Ubuntu 18.04 two machines I use, one desktop and one notebook, both started to present an occasional really slow boot and a really slow performance for everything after that boot. Both use a ...
Aldo Nogueira's user avatar
0 votes
1 answer
2k views

Ubuntu Server 18.04 SSD cache on software RAID

I have an installation consisting of 2 HDDs and 1 SSD. I want to run the 2 HDD's in a software RAID 1 with the SSD caching the array. Has somebody done this on Ubuntu Server 18.04 and if so, what were ...
Tyler McCall's user avatar
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1 answer
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Server installation fail because "bcache module not found"

When I try to install Ubuntu server 19.04-live-server-amd64 or 18.04.2-live-server-amd64, it fails because an error "bcache module not found". The bug is this, but it is closed as fixed and released. ...
angelcervera's user avatar
6 votes
1 answer
5k views

bcache for Intel Optane on ubuntu

I would like to use the Intel Optane memory (16GB) with ubuntu 18.10. My Laptop has an HDD for the OS and i thought i can use bcache for this purpose to speed up the experience. Can someone help me ...
Enjam's user avatar
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BCache + MDADM running extremely slow

I have 3x 14TB toshiba drives mdadm-ed (/dev/md0) raid 5'd together that are setup as a bcache. I have a 256GB fast SSD as the front of the bache. write-back is enabled on bcache. After a few days, ...
Chemdream's user avatar
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1 answer
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how to release device locked by bcache

Today I bought a 128MB SSD disk, installed it, then installed bcache-tools. After attempting to access the device I got these errors: root@dev:/sys/block/sda/bcache# make-bcache -B /dev/sdb1 /dev/...
Nulik's user avatar
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0 answers
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bcache performance degradation on newer version of Ubuntu kernel

I have an elasticsearch cluster which uses Azure storage with a local SSD bcache. One of the machines has poorer performance because it has cache misses while the other two machines never have cache ...
Okke's user avatar
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4 votes
1 answer
2k views

Can I use bcache without losing any data first?

My Ubuntu 17.04 (64 bit) box has: 1 x SSD (used for the OS) 2 x HDD (used for data, such as /home and backups etc.) 8GB RAM If I shrink my SSD and create an empty partition for caching my HDD(s), is ...
LogicalException's user avatar
9 votes
1 answer
487 views

Got a new SSD, don't want to wear it out but I still want to use some of it to store data files together with the old HDD

I bought a new 250GB Samsung 850 EVO SSD for my laptop that I want to use as primary storage device, together with the old but still functioning 250GB 7500 RPM HDD that I put in the former DVD bay ...
Fabio A.'s user avatar
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11 votes
2 answers
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How to install Ubuntu with both disk encryption AND SSD caching

I'm using Ubuntu in a corporate environment, and our security policy states that we have to use full disk encryption. I've also got a laptop with a 32GB mSATA SSD and 750GB of spinning rust. My ...
Adrian's user avatar
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1 vote
3 answers
3k views

Does bcache support use of an LVM logical volume as a cache device?

I've got a 64GB SSD and a 3TB hard drive in my system running Ubuntu 14.04. The SSD has a small root partition with rest of the device allocated to an LVM physical volume. From that LVM physical ...
saf's user avatar
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1 answer
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What happens in bcache if the cache ssd dies?

I'm creating a NAS and I've been doing a lot of research on the different SSD caches. I have a 120gb ssd which is more than enough for the OS so I want to use most of it as a cache for the md raid5 ...
cowmix's user avatar
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2 votes
1 answer
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Recovering disk with corrupted superblock

I am trying to recover a disk that has corrupted superblock but I cant seem to unmount the disk at all. I used bcache for the three extra drive after a reboot one of the drive stopped working. so I ...
bran's user avatar
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13 votes
3 answers
23k views

How to setup bcache?

I've tried to set up bcache in Ubuntu 14.04 with a fresh install and an empty /home partition (/dev/sdb2) as a backing device. I have a running system on my SSD and I'd like to use its /dev/sda2 ...
Laszlo Almasi's user avatar
1 vote
1 answer
708 views

bcache is not caching all drives

I have 3 HDD and 1 SSD, I have successfully mounted all drives to bcache. pavs@VAS:~$ df -h Filesystem Size Used Avail Use% Mounted on /dev/sda1 132G 35G 90G 28% / none 4....
bran's user avatar
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1 vote
1 answer
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error in bcache

I used bcache to cache my 24GB SSD using this tutorial. I tried to back up my HDD with: sudo make-bcache -B /dev/sdb1 But I get this error: Can't open dev /dev/sdb1: Device or resource busy My ...
Nimrod Padilla's user avatar
1 vote
0 answers
437 views

Bcache hangs on Ubuntu 14.04

I successfully setup my system to use bache in /home partition (200GB SSD partition as cache for 500 GB HDD partition). However, I keep receiving these messages: INFO: task bcache_writebac:222 ...
Alexandre's user avatar
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1 answer
208 views

If I convert my Ubuntu into Xen hypervizor, will I lose access to the bcache devices?

I'd like to test Xen a little. For obvious reasons I cannot do it under VirtualBox (or can I?) As I understand, Xen works by changing the kernel, thus possibly interfering with the custom kernel ...
Adam Ryczkowski's user avatar
2 votes
1 answer
9k views

"Device not found or ignored" when creating physical volume with bcache

I'm attempting to create an LVM volume on a bcache device, but getting "device not found or recognized", despite lsblk clearly showing the device, and bcache state showing "clean". OS is Ubuntu 13.10 ...
K. Darien Freeheart's user avatar
1 vote
1 answer
600 views

compressed block device

I wanted to experiment with combining bcache and a compressed block device on a hdd and seeing if this will speedup the boot time. Are there any means of compressing a block device at the block level? ...
staticd's user avatar
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1 vote
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Using btrfs with bcache on /

I am using btrfs with bcache for / on Ubuntu 13.10. It's fast. Unfortunately, during normal boots the step "Scanning for btrfs filesystems" fails. To successfully boot I have to enter recovery mode ...
joeforker's user avatar
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2 votes
3 answers
2k views

Reccomended options for mounting /dev/bcache0 as /home

I have set up /dev/sda3 on my SSD to cache /dev/sdb3 on my HDD as /dev/bcache0 using bcache in Ubuntu 13.10 (kernel 3.11.0-14-generic). I have formatted it as ext4. I currently mount / (on my SSD) ...
MattSturgeon's user avatar
1 vote
1 answer
134 views

Does using an extended cache improve performance?

Does using a extended cache (readyboost-like) improves the overall performance? I read a lot about it and some says that it's just for old machines with low RAM and also the 480mbit/s of usb2.0 was ...
Eddie's user avatar
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23 votes
2 answers
11k views

What are the advantages/disadvantages of different SSD to HDD cacheing options (dm-cache, flashcashe...)?

There appear to be various different technologies available to use an SSD to act as a cache for HHDs. The ones I know of: dm-cache (by Redhat - in the 3.9 Kernel, so it should be in ubuntu 13.10) ...
Uli's user avatar
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55 votes
4 answers
41k views

How do I install and use flashcache/bcache to cache HDD to SSD?

I want to know if there is anyone who has tried installing and running their kernel built with flashcache or bcache for SSD caching? How did you manage to do it?
kapad's user avatar
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2 votes
3 answers
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Does bcache require a fresh installation?

Because my notebook has a SSD and a HDD, I want use the SSD as cache just like Rapid Storage in windows. I find bcache offers this functionality so I decide to try it. I got bcache and bcache-tools ...
user106561's user avatar