ORACLE 19c – En Önemli 50 Wait Event

📀 I/O (Disk) Event’leri

1. db file sequential read → Tek blok okuma (index access)
2. db file scattered read → Çoklu blok okuma (full scan)
3. direct path read → PGA üzerinden direkt okuma
4. direct path write → PGA üzerinden direkt yazma
5. direct path read temp → Temp tablespace’ten okuma
6. direct path write temp → Temp’e yazma (sort/hash)
7. log file parallel write → Redo log diske yazılıyor
8. log file single write → Tek redo write
9. control file sequential read → Control file tekli okuma
10. control file parallel write → Control file yazma

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💾 Commit / Redo

11. log file sync → Commit bekliyor (çok kritik)
12. log buffer space → Redo buffer dolu
13. log file switch (checkpoint incomplete) → Checkpoint yetişmedi
14. log file switch completion → Log switch bekleniyor

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🔒 Concurrency (Lock & Latch)

15. enq: TX – row lock contention → Satır kilidi bekleme
16. enq: TM – contention → Tablo lock bekleme
17. latch: cache buffers chains → Hot block contention
18. latch free → Genel latch bekleme
19. buffer busy waits → Aynı block’a erişim çakışması
20. read by other session → Başkası okuyor, sen bekliyorsun
21. gc buffer busy acquire → RAC block contention
22. gc buffer busy release → RAC block release bekleme

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🧠 Library Cache / Parse

23. library cache lock → Obje lock bekleme
24. library cache pin → Obje kullanım bekleme
25. cursor: pin S wait on X → Cursor contention
26. cursor: mutex S → Cursor mutex bekleme
27. cursor: mutex X → Cursor exclusive mutex
28. parse time cpu → Parse CPU yoğun
29. hard parse elapsed time → Hard parse süresi

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⚙️ Configuration / Memory

30. free buffer waits → Boş buffer yok
31. checkpoint completed → Checkpoint bitmiş bekleniyor
32. write complete waits → Yazma tamamlanmamış
33. db file parallel write → DB writer yazıyor
34. DB CPU → CPU tüketimi (wait değil ama önemli)

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🌐 Network

35. SQL*Net message from client → Client bekleniyor (idle)
36. SQL*Net message to client → Client’a veri gönderiliyor
37. SQL*Net more data from client → Büyük veri geliyor
38. SQL*Net more data to client → Büyük veri gidiyor

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📊 Application

39. enq: TX – index contention → Index blok contention
40. row cache lock → Data dictionary lock
41. row cache mutex → Dictionary mutex bekleme
42. resmgr: cpu quantum → Resource Manager CPU limiti

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🧮 Temp / Sort

43. sort segment request → Temp alan allocation
44. direct path write temp → Temp’e yazma
45. direct path read temp → Temp’ten okuma

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⚡ RAC (Cluster ortamı)

46. gc cr request → RAC consistent read isteği
47. gc current request → RAC current block isteği
48. gc cr grant 2-way → RAC block transfer
49. gc current grant 2-way → RAC current transfer

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😴 Idle (Genelde sorun değil)

50. rdbms ipc message → Background process bekliyor