The benefits of a 'zdrv'
June 21, 2009 —
BarryK
I had to speed-read the forum yesterday, as I was at the Telecentre and had to do it in one hour -- didn't want to go into the second hour otherwise I have to pay for the whole extra hour.
Anyway, I noticed in the thread about my Woof-built 218, a comment about the benefit of the 'zdrv' in the original Puppy 2.x.
Yes, a 'zdrv' offers various advantages, one of which is that it makes the main SFS file smaller so bootup is faster. A second benefit of that is that if the main SFS file gets copied into RAM then it takes up less space in the RAM.
It is important to note that this is not an advantage of the old 2.x puppies, as the Woof-built puppies can also choose to be built with a 'zdrv'. In fact, Woof does it much better. The mechanism for handling a 'zdrv' in the old 2.x and 3.x puppies is klutzy, very restricted. In the old system, 'modprobe' is a script, and there are severe limitations in how it can be used. With Puppy 4.00 I overhauled that mechanism and restored the proper binary 'modprobe' executable.
In a nutshell, the old concept of having to "fetch" a module and its firmware tarball from the 'zdrv' is done away with. Instead, a zdrv is now just another SFS layer, that can be loaded when needed or not loaded -- it only needs to be loaded when there is new hardware, and modules and firmware automatically get copied-up to the save-file layer. But, it does no harm leaving it permanently as one of the layers. In other words, a transparent and much better system.
In fact, there are so many little and big improvements in Puppy since the original 2.x series, that it is no contest.
Tags: woof