Yakawanda yemahara RAM, NVMe Intel P4500 uye zvese zvinononoka zvakanyanya - iyo nyaya yekusabudirira kuwedzera kweiyo swap partition.

Muchinyorwa chino, ini ndichataura nezve mamiriro achangobva kuitika neimwe yemaseva muVPS yedu gore, iyo yakandisiya ndakagumburwa kwemaawa akati wandei. Ndanga ndichigadzirisa uye kugadzirisa maseva eLinux kweanenge makore gumi nemashanu, asi nyaya iyi haikodzeri mune yangu tsika zvachose - ndakaita fungidziro dzenhema dzakati wandei uye ndakapererwa zvishoma ndisati ndakwanisa kuona chikonzero chedambudziko nekurigadzirisa. .

Preamble

Isu tinoshandisa gore riri pakati nepakati, iro ratinovaka pamaseva akajairwa ane inotevera gadziriro - 32 cores, 256 GB RAM uye 4500TB PCI-E Intel P4 NVMe drive. Isu tinonyatsoda iyi gadziriso nekuti inobvisa kukosha kwekunetsekana pamusoro peIO nekupa iyo chaiyo kurambidzwa paVM muenzaniso mhando nhanho. Nekuti NVMe Intel P4500 ine mashandiro anokatyamadza, tinogona panguva imwe chete kupa ese ari maviri akazara IOPS kupa kumakina uye kuchengetedza kuchengetedza kune sevha yekuchengetedza ine zero IOWAIT.

Isu tiri vamwe veavo vekare vatendi vasingashandisi hyperconverged SDN uye zvimwe zvakashongedzwa, fashoni, zvinhu zvevechidiki kuchengetedza VM mavhoriyamu, tichitenda kuti iyo yakapusa sisitimu, zviri nyore kuigadzirisa mumamiriro ezvinhu e "mukuru mukuru aenda. kumakomo.” Nekuda kweizvozvo, tinochengeta VM mavhoriyamu muQCOW2 fomati muXFS kana EXT4, iyo inoiswa pamusoro peLVM2.

Isu zvakare tinomanikidzwa kushandisa QCOW2 nechigadzirwa chatinoshandisa ku orchestration - Apache CloudStack.

Kuita backup, tinotora mufananidzo uzere wevhoriyamu seLVM2 snapshot (hongu, tinoziva kuti LVM2 snapshots inononoka, asi Intel P4500 inotibatsira kunze pano futi). Tinoita lvmcreate -s .. uye nerubatsiro dd isu tinotumira iyo backup kopi kune iri kure server ine ZFS kuchengetedza. Pano isu tichiri kufambira mberi zvishoma - mushure mezvose, ZFS inogona kuchengeta data mune yakamanikidzwa fomu, uye isu tinogona kukurumidza kuidzosera tichishandisa. DD kana kuwana mavhoriyamu emunhu eVM uchishandisa mount -o loop ....

Iwe unogona, hongu, kubvisa kwete iyo yakazara mufananidzo weLVM2 vhoriyamu, asi isa iyo faira system mu RO uye kukopa mifananidzo yeQCOW2 ivo pachavo, zvisinei, takatarisana nechokwadi chokuti XFS yakava yakaipa kubva pane izvi, uye kwete pakarepo, asi nenzira isingatarisirwi. Isu hatizvifarire kana hypervisor mauto "akanamatira" kamwe kamwe pakupera kwevhiki, husiku kana pazororo nekuda kwezvikanganiso zvisiri pachena kuti zvichaitika rinhi. Naizvozvo, kune XFS isu hatishandise snapshot mounting mukati RO kuti tibvise mavhoriyamu, tinongokopa vhoriyamu yese yeLVM2.

Iko kumhanya kwekuchengetedza kune sevha yekuchengetedza kunotsanangurwa kwatiri nekuita kwesevha yekuchengetedza, iyo inenge 600-800 MB / s yedata risinganzwisisike; imwe muganhu ndiyo 10Gbit / s chiteshi iyo sevha yekuchengetedza yakabatana nayo. kuboka.

Muchiitiko ichi, makopi ekuchengetedza e8 hypervisor maseva anoiswa panguva imwe chete kune imwe backup server. Nekudaro, iyo dhisiki uye network subsystems ye backup server, ichinonoka, haibvumire dhisiki subsystems ye hypervisor mauto kuti awedzere, sezvo ivo vasingakwanise kugadzirisa, taura, 8 GB / sec, iyo iyo hypervisor mauto inogona nyore. gadzira.

Maitiro ekukopa ari pamusoro akakosha kune imwezve nyaya, kusanganisira iwo maficha - uchishandisa inokurumidza Intel P4500 drive, uchishandisa NFS uye, pamwe, uchishandisa ZFS.

Backup nyaya

Pane imwe neimwe hypervisor node isu tine diki SWAP chikamu che8 GB muhukuru, uye isu "tinoburitsa" iyo hypervisor node pachayo tichishandisa. DD kubva pamufananidzo wereferensi. Kune iyo system vhoriyamu pamaseva, tinoshandisa 2xSATA SSD RAID1 kana 2xSAS HDD RAID1 pane LSI kana HP hardware controller. Kazhinji, isu hatina hanya zvachose nezviri mukati, sezvo vhoriyamu yedu inoshanda mu "inenge yekuverenga chete" modhi, kunze kweSWAP. Uye sezvo isu tine yakawanda RAM pane sevha uye iri 30-40% yemahara, isu hatifunge nezve SWAP.

Backup process. Iri basa rinotaridzika seizvi:

#!/bin/bash

mkdir -p /mnt/backups/volumes

DIR=/mnt/images-snap
VOL=images/volume
DATE=$(date "+%d")
HOSTNAME=$(hostname)

lvcreate -s -n $VOL-snap -l100%FREE $VOL
ionice -c3 dd iflag=direct if=/dev/$VOL-snap bs=1M of=/mnt/backups/volumes/$HOSTNAME-$DATE.raw
lvremove -f $VOL-snap

teerera ionice -c3, kutaura zvazviri, chinhu ichi hachina basa zvachose kune NVMe zvishandiso, sezvo iyo IO scheduler kwavari yakaiswa se:

cat /sys/block/nvme0n1/queue/scheduler
[none] 

Nekudaro, isu tine akati wandei enhaka node ane akajairwa SSD RAID, kwavari izvi zvine basa, saka vari kufamba. AS IS. Pakazara, ichi chingori chidimbu chinonakidza chekodhi chinotsanangura zvisina maturo ionice kana paine gadziriro yakadaro.

Teerera mureza iflag=direct nokuti DD. Isu tinoshandisa yakananga IO kunzvenga buffer cache kuti tidzivise kutsiva kusingaite kweIO mabuffers pakuverenga. Zvisinei, oflag=direct hatidaro nekuti takasangana nenyaya dzeZFS pakushandisa.

Tave tichishandisa chirongwa ichi zvinobudirira kwemakore akati wandei pasina matambudziko.

Zvino zvakabva zvatanga... Takaona kuti imwe yemanodhi yakanga isisiri kutsigirwa, uye yekutanga yakanga ichimhanya neIOWAIT inotyisa ye50%. Pakuedza kunzwisisa kuti sei kukopa kusingaitike, takasangana neinotevera chiitiko:

Volume group "images" not found

Takatanga kufunga nezve "kuguma kwasvika kuIntel P4500," zvisinei, tisati tadzima sevha kutsiva dhiraivha, zvaive zvichiri madikanwa kuita backup. Isu takagadzirisa LVM2 nekudzoreredza metadata kubva kuLVM2 backup:

vgcfgrestore images

Takatanga backup uye takaona iyi pendi yemafuta:

Zvakare takanga takasuruvara zvikuru - zvaiva pachena kuti isu taisagona kurarama seizvi, sezvo vose veVPS vaizotambura, izvo zvinoreva kuti isu taizotamburawo. Zvakaitika hazvina kujeka zvachose - iostat yakaratidza IOPS inosiririsa uye yepamusorosoro IOWAIT. Pakanga pasina mazano kunze kwe "ngatitsivai NVMe," asi nzwisiso yakaitika panguva chaiyo.

Ongororo yemamiriro ezvinhu nhanho nhanho

Historical magazine. Mazuva mashoma apfuura, pane iyi sevha zvaive zvakafanira kugadzira VPS yakakura ine 128 GB RAM. Pakaita sekunge paine ndangariro dzakakwana, asi kuti tive parutivi rwakachengetedzeka, takagovera imwe 32 GB yekuparadzanisa. VPS yakagadzirwa, yakabudirira kupedza basa rayo uye chiitiko chacho chakakanganwika, asi chikamu cheSWAP chakasara.

Configuration Features. Kune ese cloud servers parameter vm.swappiness yakaiswa ku default 60. Uye SWAP yakagadzirwa paSAS HDD RAID1.

Chii chakaitika (maererano nevapepeti). Paunenge uchitsigira DD yakagadzira yakawanda yekunyora data, iyo yakaiswa mu RAM buffers isati yanyorera kuNFS. System musimboti, inotungamirwa nepolicy swappiness, yaifambisa mapeji akawanda eVPS ndangariro kunzvimbo yekuchinjana, yaive iri pane inononoka HDD RAID1 vhoriyamu. Izvi zvakaita kuti IOWAIT ikure zvakasimba, asi kwete nekuda kweIO NVMe, asi nekuda kweIO HDD RAID1.

Dambudziko rakagadziriswa sei. Iyo 32GB swap partition yakavharwa. Izvi zvakatora maawa gumi nematanhatu; unogona kuverenga zvakasiyana kuti sei uye nei SWAP ichidzima zvishoma nezvishoma. Settings dzachinjwa swappiness pamutengo wakaenzana ne 5 mugore rose.

Izvi zvaisagona kuitika sei?. Chekutanga, dai SWAP yanga iri paSSD RAID kana NVMe mudziyo, uye kechipiri, dai pasina NVMe mudziyo, asi inononoka mudziyo waisaburitsa huwandu hwakadaro hwe data - zvinoshamisa, dambudziko rakaitika nekuti iyo NVMe inokurumidza.

Pashure pacho, zvose zvakatanga kushanda sepakutanga - ne zero IOWAIT.

Source: www.habr.com