>
> If you had more vnodes per
> machine, you could stream more ranges in parallel, taking advantage of more
> cores, streaming significantly faster. This is a very real gain if you are
> regularly adding or removing a FEW nodes.
In our experience 16 vnodes for streaming is much like 256. You tend
That is good info. Thanks.
George
On Mon, Oct 9, 2017 at 10:23 AM, Jeff Jirsa wrote:
> One of my very smart coworkers who rarely posts to the list pointed out
> privately that I've oversimplified this, and there are other advantages to
> having more vnodes SOMETIMES.
>
> In particular: most of o
One of my very smart coworkers who rarely posts to the list pointed out
privately that I've oversimplified this, and there are other advantages to
having more vnodes SOMETIMES.
In particular: most of our longest streaming operations
(bootstrap/decommission/removenode) are cpu bound on the stream r
As long as balanced is achieved, fewer vnodes the better
--
Jeff Jirsa
> On Oct 9, 2017, at 7:53 AM, Li, Guangxing wrote:
>
> Jeff,
>
> so the key really is to keep nodes load balanced, and as long as that such
> balance is achieved, using a smaller amount of vnodes does not have other
> ne
Jeff,
so the key really is to keep nodes load balanced, and as long as that such
balance is achieved, using a smaller amount of vnodes does not have other
negative impact?
Thanks.
George
On Mon, Oct 9, 2017 at 8:46 AM, Jeff Jirsa wrote:
> 256 was chosen because the original vnode allocation a
256 was chosen because the original vnode allocation algorithm was random and
fewer than 256 could lead to unbalanced nodes
In 3.0 there’s a less naive algorithm to ensure more balanced distribution, and
there 16 or 32 is probably preferable
--
Jeff Jirsa
> On Oct 9, 2017, at 7:38 AM, Li,
Hi,
the documentation says that '...The recommended initial value for
num_tokens is 256...' and this is what we did with our cluster which is
running Cassandra Community 2.0.9, has 3 physical nodes with replication
factor 3 for all keyspaces, each with 256 vnodes, each physical node has
about 96 G
