5 sec boot

NoiseEHC NoiseEHC at freemail.hu
Sun Oct 5 13:16:44 EDT 2008


> On Sun, 5 Oct 2008, NoiseEHC wrote:
>
>>> can you do the hash as you copy it? it should be pretty close to 
>>> free at that point (since the CPU is waiting for memory/flash access 
>>> it can do the hash calculationwhen it would otherwise be stalled)
>>>
>>>
>> According to my measurements the GeodeLX can fetch a new cache line 
>> (32 bytes) every 20-25 clocks.
>> Unless you can do the hash <2 clocks/byte then you will only earn the 
>> looping time (assuming that the hashed blocks fit into the L1 cache).
>
> is that speed reading from ram or from flash?
>
>
DDR RAM, if neither the L1 nor L2 was hit. I did not measure raw NAND 
read speed, I do not even know how to begin with it.
see:
http://wiki.laptop.org/go/Geode_LX#Memory.2C_Cache_and_TLB




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