Attention

This is the documentation for HARP Proxy, actually published as an early preview. Both the software and documentation are a work in progress, and although we already use it on various production servers, they may contain inaccuracies, typographical errors, huge mistakes and empty pages. We work hard to eradicate all mistakes and implement stuff, but it is a long and tedious process. We appreciate your patience and understanding. Of course, any help will be greatly appreciated.

Performances

Transaction performances are evaluated based on response time (Time to Last Byte or TTLB), which is converted into a score from 0 to 100 (higher is better). We call this rating TPDEX (Transaction Performance Index).

This score is then converted into a letter rating for display.

Response time (TTLB) to Transaction Performance Index (TPDEX)

• Y Axis: TPDEX

• X Axis: TTLB in milliseconds

Letter Rating

TPDEX threshold	Response time threshold		Rating
98	25ms		A++
96	50ms		A+
93	100ms		A
83	250ms		B
69	500ms		C
49	1s		D
31	2s		E
17	4s		F
0	∞		G