Menene cikakken sunan Redis RDB? Redis RDB bayanan ƙwaƙwalwar ajiya yanayin dagewar aiki

Cikakken sunan RDB shineRedis database.

• Kamar yadda sunan ke nunawa, RDB shine bayanan Redis da ake amfani dashi don adana bayanai.
• Saboda haka, ta hanyar dagewar RDB, ana rubuta bayanan da aka adana a cikin ƙwaƙwalwar ajiyar Redis zuwa fayil ɗin RDB kuma an adana su zuwa faifai don samun nacewa.
• Siffar Redis ita ce tana iya jurewa bayanai, wato, rubuta bayanai a ƙwaƙwalwar ajiya zuwa faifai don tabbatar da cewa babu bayanai da suka ɓace, kuma yana iya loda bayanai daga faifai zuwa ƙwaƙwalwar ajiya.

Ayyukan Redis a farkon duk sun dogara ne akan ƙwaƙwalwar ajiya, don haka aikin yana da girma sosai, amma da zarar an rufe shirin, bayanan sun ɓace.

Don haka, muna buƙatar rubuta bayanan ƙwaƙwalwar ajiya zuwa faifai a ƙayyadaddun tazara, wanda shine Snapshot a cikin jargon.

Lokacin da ake dawowa, ana rubuta fayil ɗin hoton kai tsaye zuwa ƙwaƙwalwar ajiya.

Wannan kuma shine ɗayan manyan bambance-bambance tsakanin Redis da Memcached, saboda Memcached ba shi da ƙarfin dagewa.

Don dorewar bayanan ƙwaƙwalwar ajiya na Redis, Redis yana ba mu hanyoyi masu zuwa:

• Hanyar daukar hoto (RDB, Redis DataBase): rubuta bayanan ƙwaƙwalwar ajiya zuwa faifai a cikin nau'i na binary a wani ɗan lokaci;
• Ƙara Fayil Kawai (AOF, Fayil ɗin Ƙara kawai), yin rikodin duk umarnin aiki, kuma sakawa fayil ɗin a cikin sigar rubutu;
• Dagewar matasan, sabuwar hanya bayan Redis 4.0, dagewar matasan ta haɗu da fa'idodin RDB da AOF.Lokacin rubutawa, da farko rubuta bayanan yanzu zuwa farkon fayil ɗin a cikin hanyar RDB, sannan adana umarnin aiki na gaba zuwa fayil ɗin a cikin nau'in AOF, wanda ba zai iya tabbatar da saurin Redis sake kunnawa ba, amma kuma ya rage. hadarin data hasarar .

Domin kowane tsarin dagewar yana da takamaiman yanayin amfani.

Redis RDB bayanan ƙwaƙwalwar ajiya yanayin dagewar aiki

• RDB (Redis DataBase) shine tsarin rubuta hoton ƙwaƙwalwar ajiya (Snapshot) a wani lokaci zuwa faifai a cikin nau'i na biyu.
• Hoton ƙwaƙwalwar ajiya shine abin da muka faɗa a sama.Yana nufin rikodin bayanai a cikin ƙwaƙwalwar ajiya a wani lokaci.
• Wannan yana kama da ɗaukar hoto, lokacin da kuka ɗauki hoton aboki, hoto na iya yin rikodin duk hotunan aboki nan take.
• Akwai hanyoyi guda biyu don kunna RDB: ɗayan yana jawo hannun hannu, ɗayan kuma ta atomatik.

Fara RDB da hannu

Akwai ayyuka guda biyu don jawo dagewa da hannu:savekumabgsave.

Babban bambanci tsakanin su shine ko a toshe aiwatar da babban zaren Redis ko a'a.

1. ajiye umarni

Yin aiwatar da umarnin adanawa a gefen abokin ciniki zai haifar da dagewar Redis, amma kuma zai sanya Redis cikin yanayin toshewa. yanayin samarwa.

127.0.0.1:6379> save
OK
127.0.0.1:6379>

Ana nuna tsarin aiwatar da umarnin a cikin adadi 

2. umarnin bgsave

• bgsave (ajiya ta baya) ajiyar bango ce.
• Babban bambanci tsakaninsa da umarnin ajiyewa shine cewa bgsave zai cokali tsarin yaro don yin nacewa.
• Dukan tsari yana faruwa ne kawai lokacin da tsarin yaro ya zama cokali mai yatsa.Akwai taƙaitaccen toshewa kawai.
• Bayan an ƙirƙiri tsarin yaran, babban tsarin Redis na iya amsa buƙatun wasu abokan ciniki.

tare da toshe dukkan tsarisaveidan aka kwatanta da umarninbgsaveBabu shakka Umurni ya fi dacewa da mu don amfani.

127.0.0.1:6379> bgsave
Background Saving started # 提示开始后台保存 
127.0.0.1:6379>

Fara RDB ta atomatik

Bayan magana game da jawo hannun hannu, bari mu kalli fararwa ta atomatik.Za mu iya saita yanayi don kunnawa ta atomatik a cikin fayil ɗin sanyi.

1. ajiye mn

• Save mn yana nufin cewa a cikin daƙiƙa m, idan n maɓallan sun canza, dagewar na faruwa ta atomatik.Ana iya samun madaidaicin m da n a cikin fayil ɗin daidaitawar Redis.
• Misali, ajiye 60 1 yana nufin cewa a cikin daƙiƙa 60, muddin maɓalli ɗaya ya canza, juriyar RDB za ta jawo.
• Ma'anar haifar da dagewa ta atomatik shine idan an cika ka'idodin da aka saita, Redis zai aiwatar da umarnin bgsave ta atomatik sau ɗaya.

Lura: Lokacin da aka saita umarni da yawa na ajiye mn, kowane yanayi zai haifar da dagewa.

Misali, mun saita umarni biyu na ajiye mn:

save 60 10
save 600 20

• Lokacin da ƙimar maɓallin Redis ta canza sau 60 a cikin 10s, za a jawo dagewa;
• Idan maɓallin Redis ya canza a cikin 60s, kuma idan darajar ta canza ƙasa da sau 10, to, Redis zai ƙayyade ko an canza maɓallin Redis aƙalla sau 600 a cikin 20s, kuma idan haka ne, yana haifar da dagewa.

2. Flushall

• Ana amfani da umarnin flushall don zubar da bayanan Redis.
• Dole ne a yi amfani da shi da hankali a cikin yanayin samarwa.
• Lokacin da Redis ya aiwatar da umarnin flushall, yana haifar da juriya ta atomatik kuma yana share fayilolin RDB.

3. Jagora-bawa yana jawo aiki tare

A cikin Redis master-slave kwafi, lokacin da kullin bawa ya yi cikakken aikin kwafi, maigidan zai aiwatar da umarnin bgsave don aika fayil ɗin RDB zuwa kumburin bawa. Wannan tsari ta atomatik yana haifar da nacin Redis.

Redis na iya tambayar sigogin sanyi na yanzu ta hanyar umarni.

Tsarin umarnin tambayar shine:config get xxx

Misali, idan kuna son samun saitin sunan ajiya na fayil ɗin RDB, zaku iya amfani dashi config get dbfilename .

Tasirin aiwatarwa shine kamar haka:

127.0.0.1:6379> config get dbfilename
1) "dbfilename"
2) "dump.rdb"

Tunda uwar garken Redis zai toshe lokacin loda fayil ɗin RDB har sai an gama lodawa, yana iya haifar da dogon lokaci kuma ba za a iya shiga gidan yanar gizon ba.

Idan kuna son share fayil ɗin cache na RDB da hannu dump.rdb na Redis, zaku iya amfani da wannan umarni don nemo hanyar ajiya na fayil ɗin dump.rdb▼

find / -name dump.rdb

• Sa'an nan, da hannu share dump.rdb cache fayil ta hanyar SSH.

Redis yana saita saitin RDB

Game da saitin daidaitawar RDB, zaku iya amfani da hanyoyi biyu masu zuwa:

1. Gyara fayil ɗin sanyi na Redis da hannu
2. Yi amfani da saitunan layin umarni, saita saitin dir "/ usr/data" shine umarnin ajiya don gyara fayil ɗin RDB

Lura: Za'a iya samun tsarin daidaitawa a cikin redis.conf ta hanyar daidaitawa samun xxx kuma an gyara ta ta hanyar saita saita darajar xxx, kuma hanyar da za a gyara fayil ɗin daidaitawar Redis da hannu yana da tasiri a duniya, wato, sigogin da aka saita ta hanyar sake kunna uwar garken Redis ba zai yiwu ba. a ɓace, amma an gyara ta amfani da umarnin, zai ɓace bayan Redis ya sake farawa.

Koyaya, idan kuna son gyara fayil ɗin sanyi na Redis da hannu don aiwatarwa nan da nan, kuna buƙatar sake kunna sabar Redis, kuma hanyar umarni baya buƙatar sake kunna uwar garken Redis.

RDB fayil dawo da

Lokacin da uwar garken Redis ya fara, idan fayil ɗin RDB dump.rdb ya kasance a cikin Redis tushen directory, Redis zai loda fayil ɗin RDB ta atomatik don dawo da bayanan dagewa.

Idan babu fayil dump.rdb a cikin tushen directory, da fatan za a matsar da dump.rdb fayil zuwa tushen directory na Redis farko.

Tabbas, akwai bayanan log lokacin da Redis ya fara, wanda zai nuna ko an loda fayil ɗin RDB.

Sabar Redis tana toshewa yayin loda fayil ɗin RDB har sai an gama lodawa.

Yanzu mun san cewa dagewar RDB ya kasu kashi biyu: fararwa ta hannu da ta atomatik:

1. Amfaninsa shine cewa fayil ɗin ajiya yana da ƙananan kuma dawo da bayanai yana da sauri lokacin da aka fara Redis.
2. Abinda ya rage shine cewa akwai haɗarin asarar bayanai.

Maido da fayilolin RDB shima abu ne mai sauqi, kawai sanya fayilolin RDB a cikin tushen directory na Redis, kuma Redis zai loda da dawo da bayanan kai tsaye idan ya fara.

RDB ribobi da fursunoni

1) RDB abũbuwan amfãni

Abubuwan da ke cikin RDB sune bayanan binary, wanda ke ɗaukar ƙarancin ƙwaƙwalwar ajiya, ya fi ƙanƙanta, kuma ya fi dacewa azaman fayil ɗin ajiya;

RDB yana da amfani sosai don dawo da bala'i, fayil ne mai matsawa wanda za'a iya canjawa wuri zuwa uwar garken nesa da sauri don dawo da sabis na Redis;

RDB na iya inganta saurin Redis sosai, saboda babban tsarin Redis zai fara aiwatar da tsarin yaro don dagewar bayanai zuwa faifai.

Babban tsarin Redis baya yin ayyuka kamar diski I/O;

Idan aka kwatanta da fayilolin tsarin AOF, fayilolin RDB suna sake farawa da sauri.

2) Rashin RDB

Saboda RDB na iya adana bayanai kawai a wani tazara na lokaci, idan sabis ɗin Redis ya ƙare da gangan a tsakiya, bayanan Redis za su ɓace na ɗan lokaci;

Tsarin da RDB ke buƙatar yawan cokali mai yatsu don adana shi akan faifai ta amfani da subentry.

Idan bayanan yana da girma, cokali mai yatsa na iya ɗaukar lokaci, kuma idan bayanan yana da girma, aikin CPU ba shi da kyau, wanda zai iya sa Redis ya kasa yin hidima ga abokan ciniki na ƴan milliseconds ko ma daƙiƙa guda.

Tabbas, zamu iya kuma musaki dagewa don inganta ingantaccen aiwatar da Redis.

Idan ba ku kula da asarar bayanai, kuna iya yin hakan lokacin da abokin ciniki ya haɗu config set save "" Umarni don musaki dagewar Redis.

Aredis.conf, idan a cikisaveFitar da duk saitunan da aka yi a farkon, kuma dagewar kuma za a kashe, amma wannan gabaɗaya ba a yi ba.