Usemsebenzini ongalindelekile wesevisi yewebhu: isilinganisi somthwalo phambi kwesikhwama sezimo, i-cache phambi kwesizindalwazi, nenhloso yokutholakala engu-99.9 %. Umzuzu ngamunye imodeli ibala ukubambezeleka kokuhleleka, ama-timeout, ukushaya kwe-cache nomthwalo wesizindalwazi ngamafomula ezincwadi — nokuthi izinqumo zakho zibiza malini.
Isisekelo sesikhwama. Ukusikhuphula kuqala izimo ngokushesha — zisadinga ukubambezeleka kokuqala ngaphambi kokusebenzela.
Ukulandela inhloso ekusetshenzisweni; akukho ukukala okusha uma izimo zisaqala. Kuvaliwe = ubuncane kanye.
Phansi = isikhala esiningi nezindleko eziningi. Ukusetshenziswa okulinganisiwe akunakudlula u-100 %, ngakho-ke isikhwama esigcwele sikhula ngezinyathelo kuphela.
I-TTL ende = ukushaya okuningi, kodwa izimpendulo zingaba zindala (iminyaka ephakathi ≈ TTL/2).
Ilayisha okhiye abashisayo imizuzu eyi-6 (+12 % ye-cache ngomzuzu) ngenani lemibuzo yesizindalwazi eyengeziwe engu-600/s.
Ingxenye ye-30 % yokubaluleka okuphansi (ukulayisha kuqala, i-batch, ama-crawler) ewiswa ekulinganiseni komthwalo ngo-"zama kamuva".
Isici esinzima sengeza u-20 ms we-CPU kanye nombuzo owodwa wesizindalwazi ngesicelo ngasinye. Kuvaliwe = ukwehla okuhloniphekile.
Kuphinda kuthumele i-build elungile yokugcina kumkhomba omusha (imizuzu emi-5, kubiliswa kabili), bese kushintsha ithrafikhi. Ukucindezela futhi kuqala kabusha ukulungiselela; uma kungekho i-build embi ephilayo kubiza imali kuphela.
| Izinga lokushisa (1 h) | 0.0 × |
|---|---|
| Izicelo | 1125 req/s |
| Izimo ezisebenzela | 10 |
| Izimo ezisaqala | 0 |
| Izinga lokushaya le-cache | 77 % |
| Ukusetshenziswa kwesizindalwazi | 19 % |
| Ithrafikhi elahliwe | 0 % |
| Izindleko zesikhwama | 4.00 $/h |
| Izindleko kuze kube manje | 0.00 $ |
| Iminyaka ephakathi yezimpendulo ze-cache | 30 s |
| Ithrafikhi ekwakhiweni okubi | 0 % |
| Izincomo ziyatholakala | 100 % |
Ukwakhiwa okusha kuphumela ngo-09:10. Inyanga isivele inzima: u-20 % kuphela wohlahlo-mali lwamaphutha osele. Imizuzu ngemva kokufakwa, ikhasi lezinga lokushisa liyadubula. Vikela uhlahlo-mali.
Isixhumanisi sesevisi sisakazeka ngokushesha futhi kulindeleke ukunyuka kwethrafikhi ngesinye isikhathi ekuseni namuhla — akekho owaziyo nini, noma ukuthi kukhulu kangakanani. Namuhla ama-instance (amaseva amasha) adinga imizuzu engu-8 ukuqala. Uma efika, gcina amaphutha nokulibaza kuphansi ngaphandle kokushisa imali ekumthamo ongasebenzi.
Esiqongweni sasemini iskripthi sokulungisa sikhipha yonke i-cache. Isicelo ngasinye manje siya esizindalwazini, esenzelwe izinga elivamile lokushaya elingu-85 %. Buyisela isevisi ngaphandle kokweqisa umthwalo wesizindalwazi.
Wonke ubudlelwano isilingisi esibusebenzisayo, nomthombo wabo. Izinto ezihlala zingashintshi ezimakwe njengokuthathelwa yizilinganiso zesibonelo.
λ(t) = base × (1 + 0.25·sin(2π(t + clock − 6 h)/24 h)) × surge(t), clock = time of day at the start (peak at 12:00); count/min ≈ N(60λ, √(60λ)) × (1 + N(0, 0.02))[6]Umcabango: inani labasebenzi, izikhathi zensizakalo, umthamo wesizindalwazi, usayizi we-cache, isivinini sokugcwalisa, amanani nezinga lamaphutha okwakhiwa okubi ayizinani zokufanekisa zesevisi yewebhu ephakathi nendawo.N = instances × 16 workers, a = λ·S; C(a, N) = B / (1 − (a/N)(1 − B)), B = Erlang B[3][6]P(W > t) = C·e^(−(N/S − λ)·t); timeouts = P(W > 2 s); a ≥ N ⇒ failed share = 1 − N/a[3]p99 ≈ S·ln 100 + ln(C/0.01)/(N/S − λ) (service + waiting quantile, an approximation)[3][6]Isilinganiso: ukungeza ama-quantile ensizakalo nokulinda akulona i-p99 eqondile yesamba sawo (lingaba phezulu noma phansi kancane); umugqa uphathwa njengozinzile kuwo wonke umzuzu ngoba izicelo zithatha ama-millisecond.busy workers L = λ·S ⇒ utilization = λ·S / N[4]hit = warm × rT/(1 + rT), r = λ / 20,000 objects; mean age of a cached answer ≈ T/2[5]DB load = λ·q·(1 − hit); query time = 5 ms/(1 − ρ_db) (≤ 250 ms); S = S_app + (1 − hit)·q·query time[6]Umcabango: inani labasebenzi, izikhathi zensizakalo, umthamo wesizindalwazi, usayizi we-cache, isivinini sokugcwalisa, amanani nezinga lamaphutha okwakhiwa okubi ayizinani zokufanekisa zesevisi yewebhu ephakathi nendawo.budget = 1 − SLO = 0.1 %; burn = error rate / 0.1 %; Δbudget per min = burn / 43,200; burn (1 h) = mean error rate over the last 60 min / 0.1 % (window pre-filled with the opening minute)[1][2]desired = ⌈serving × utilization / target⌉ (utilization saturates at 100 %); new instances serve after the boot delay[6]Umcabango: inani labasebenzi, izikhathi zensizakalo, umthamo wesizindalwazi, usayizi we-cache, isivinini sokugcwalisa, amanani nezinga lamaphutha okwakhiwa okubi ayizinani zokufanekisa zesevisi yewebhu ephakathi nendawo.16 workers/instance · app time 50 ms (+20 ms and +1 query with the feature on) · 2 queries/request · DB 4,000 queries/s · 20,000 hot objects · cache refill τ = 30 min (slower while the DB is saturated) · warm-up job +12 %/min for 6 min, +600 queries/s · timeout 2 s · 30 % low-priority traffic · bad build +5 % errors, ×1.25 CPU · rollback 5 min · $0.40 per instance-hour · scale-in by ≤ 20 % of the fleet after 10 quiet minutes · up to 40 instancesUmcabango: inani labasebenzi, izikhathi zensizakalo, umthamo wesizindalwazi, usayizi we-cache, isivinini sokugcwalisa, amanani nezinga lamaphutha okwakhiwa okubi ayizinani zokufanekisa zesevisi yewebhu ephakathi nendawo.Ukungahleliwe: i-generator ye-mulberry32 enembewu; ukusabalalisa okusetshenzisiwe — uniform, exponential (inverse CDF), normal (Box–Muller), Poisson (Knuth). Imbewu iyabonisa futhi ingabelwana.
Imodeli yemfundo — hhayi yezinqumo zokusebenza. Izindawo zangempela zilinganisa yonke into ehlala ingashintshi kumishini nedatha yazo.