Hello!
imho placing fossil, venti, isect, bloom and swap on single drive is bad idea.
As written in in
http://plan9.bell-labs.com/sys/doc/venti/venti.html - "
The prototype Venti server is implemented for the Plan 9 operating system in about 10,000 lines of C. The server runs on a dedicated dual 550Mhz Pentium III processor system with 2 Gbyte of memory and is accessed over a 100Mbs Ethernet network. The data log is stored on a 500 Gbyte MaxTronic IDE Raid 5 Array and the index resides on a string of 8 Seagate Cheetah 18XL 9 Gbyte SCSI drives."
God ide is to store isect on multiple SSD drives :) to speed up search.
My small installation - 80Gb (PATA) 9fat, fossil, swap + 40Gb isect, bloom drive (PATA) + 1Tb SATA as arenas. No RAID.