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Questions tagged [flashcache]

10 questions
24
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2 answers

Linux SSD as HDD cache

I have a Linux server system installed on an SSD and an HDD for user data. As there is space left on the SSD, I want to use it as a read cache for the HDD. Looking at the possibilities, I found: dm-cache: Needs a lot of reads before caching shows…
GxB
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14
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4 answers

Improving IO with FlashCache

I have a server with 2 HDD's (2x 1 TB), running in RAID 1 (SW-RAID). I want to improve IO performance by using flashcache. There are running KVM virtual machines on it, using LVM. Regarding this, I have the following questions: Will this even work?…
Devator
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4
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2 answers

Using FlashCache on /var on startup

I would like to have FlashCache cache my /var partition however I can't seem to get it to play nice upon bootup (IE: not really sure how to do it). I'm not sure if I need to modify the initramfs/use DKMS or if I can do it in user-land during bootup.…
WinkyWolly
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3
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1 answer

flashcache with mdadm and LVM

I am having trouble setting up flashcache on a system with LVM and mdadm, I suspect I am either just missing an obvious step or getting some mapping wrong and hoped someone could point me in the right direction? system info: CentOS 6.4 64 bit mdadm…
Backtogeek
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2
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1 answer

Possible to use /dev/mapper in custom initrd (CentOS/RHEL)?

I'm attempting to setup a mapper device prior to boot as it requires use of my /var partition which is relied heavily upon startup. My issue is it's seemingly failing and not providing any output - I'm unsure if this is something I'm doing terribly…
WinkyWolly
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1
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1 answer

RAID1 LVM, XEN and flashcache

I am regarding to question: Improving IO with FlashCache I have setup a RAID1 (/dev/md0) LVM (/dev/vg_xen) and executed following command: flashcache_create -p thru flashcache0 /dev/sdc /dev/md0 Then I started a XEN PV guest, which uses…
user1091344
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2 answers

What kind of performance overhead with LVM on Fusion ioDrive2 as Oracle DB 11gR2's Flash Cache?

This is a bit wordy, so please bear with me. :) We have a RAC cluster of 3 Oracle 11gR2 servers and purchased FusionIO ioDrive2 PCIx cards for these servers to use as OracleDB's Flash Cache. These servers run both our production db instance and a…
Mxx
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0
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1 answer

Using Facebook's Flashcache on root partition (/)

I'm tring to implement Flashcache for a root particion for an ubuntu box. There is an excellent doc how to do this in flashcache: https://github.com/facebook/flashcache/blob/master/README-DKMS My problem is at this line: Edit your /etc/fstab and…
EdgarPE
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1 answer

SSD DD write speed lower than HDD

I've come across a strange phenomena with a new dedicated server that's been provisioned. The server has 2x1TB HDDs in software RAID 1 and a separate 120GB SSD that is intended to be used as a FlashCache drive. Both the spinning disks and the SSD…
rich1334
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3 answers

Flashcache Power Failure

iam using ssd for caching other disks ( flashcache module ) if a power failure happened write operations will just stop suddenly and lead to bad sector due to incomplete cache back to devices ( sata disks ) so is there is a way to continue get cache…
user205537
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