File:Graid-performance.png

Chart showing performance of graid3 and gmirror (and some proprietary RAID1 hardware implementations).

System: 
   amd64 6.2-RELEASE, Athlon X2 5000+, 2GB RAM
   3x Western Digital 250GB drives (WDC WD2500JS-22NCB1 10.02E02 SATA-300)
   2x Western Digital 500GB drives (WDC WD5000AAKS-00YGA0 12.01C02)
   Nvidia nForce onboard RAID controller, Promise TX2300 RAID controller

Each process shown in the graph is a cp to /dev/null of an individually generated 3200MB random binary file (using dd if=/dev/random bs=16m count=200).

The "split" balance algorithm for gmirror was also tested but resulted in universally horrible performance, so was not included on the graph. The "-r" option (use parity drive on reads) for graid3 was also tested but typically resulted in slight to severe performance decrease, so was not included on the graph.

Raw data follows:

Graid3: 3x250/2x500			213	137	106	105	105		
Graid3: 3x250/2x500 -r			187	144	103	105	107		
Nvidia onboard RAID1: 2x250		60	108	90	96	100	* 15 secs delta on 2-process copy / 38 seconds on 5-process!
Graid3: 3x250 -r			116	88	79	76	75		
Graid3: 3x250				115	98	77	76	75		
Baseline: 1x500			76	70	72	72	72		
Gmirror: 3x250/2x500 round-robin	63	73	69	71	72		
Promise TX-2300 RAID1: 2x250		61	52	54	55	57	* 15 sec delta on 5-process copy
Gmirror: 3x250 round-robin		59	53	53	56	55		
Gmirror: 2x250 round-robin		58	49	51	51	50		
Baseline: 1x250			56	56	55	55	56		
Gmirror: 3x250 split 128k		55	46	49	55	54		
Gmirror: 2x250 split 128k		55	47	47	47	48		
Gmirror: 3x250/2x500 split 128k	54	50	47	47	47

"Delta" in raw numbers refers to individual processes finishing significantly faster than others, though all were started simultaneously.