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Re: ByteOrdered partitioner when using sha-1 as partition key

The time it takes to calculate the hash is so insignificant that it doesn't even remotely come close to justifying all the drawbacks. 

You can, of course, benchmark it. I wouldn't bother though. BOP is basically dead. 

On Sat, Feb 11, 2017 at 10:47 AM Micha <micha-1@xxxxxxxxxxxxxx> wrote:
I think I was not clear enough...

I have *one* table for which the row data contains (among other values)
a sha-1 sum. There are no collisions.  I thought computing a murmur hash
for a sha-1 sum is just wasted time, as the murmur hash doesn't make the
data more random than it already is.   So it's just one table where this


Am 11.02.2017 um 16:54 schrieb Jonathan Haddad:
> The odds of only using a sha1 as your partition key for every table you
> ever create is low. You will regret BOP until the end of time.
> On Sat, Feb 11, 2017 at 5:53 AM Edward Capriolo <edlinuxguru@xxxxxxxxx
> <mailto:edlinuxguru@xxxxxxxxx>> wrote:
>     Probably best to avoid bop even if you are aflready hashing keys
>     yourself. What do you do when checksuma collide? It is possible right?
>     On Saturday, February 11, 2017, Micha <micha-1@xxxxxxxxxxxxxx
>     <mailto:micha-1@xxxxxxxxxxxxxx>> wrote:
>         Hi,
>         my table has a sha-1 sum as partition key. Would in this case the
>         ByteOrdered partitioner be a better choice than the
>         Murmur3partitioner,
>         since the keys are quite random?
>         cheers,
>          Michael
>     --
>     Sorry this was sent from mobile. Will do less grammar and spell
>     check than usual.