Wait Event	R/W	Synchronous /Asynchronous	Singleblock/ Multiblock	Elapsed Time (with 1000+ waits per hour)
control file parallel write	Write	Asynchronous	Multi	< 15ms
control file sequential read	Read	Synchronous	Single	< 20 ms
db file parallel read	Read	Asynchronous	Multi	< 20 ms
db file scattered read	Read	Synchronous	Multi	< 20 ms
db file sequential read	Read	Synchronous	Single	< 20 ms
direct path read	Read	Asynchronous	Multi	< 20 ms
direct path read temp	Read	Asynchronous	Multi	< 20 ms
direct path write	Write	Asynchronous	Multi	< 15 ms
direct path write temp	Write	Asynchronous	Multi	< 15 ms
log file parallel write	Write	Asynchronous	Multi	< 15 ms

Exadata Related

cell smart table scan	Read	Asynchronous	Multi	< 1 ms
cell single block physical read	Read	Synchronous	Single	< 1 ms
cell multiblock physical read	Read	Synchronous	Multi	< 6 ms

ITPub博客

【WAIT】wait event