On Fri, 14 Mar 2014 05:35:03 -0400, Don <x...@nospam.com> wrote:
On Thursday, 13 March 2014 at 13:47:13 UTC, Steven Schveighoffer wrote:
On Thu, 13 Mar 2014 09:37:51 -0400, Dicebot <pub...@dicebot.lv> wrote:
On Thursday, 13 March 2014 at 13:16:54 UTC, Daniel Murphy wrote:
"Steven Schveighoffer" wrote in message
news:op.xcnu55j2eav7ka@stevens-macbook-pro.local...
> The worst breaking change in D2, by far, is the prevention
> > of
array stomping.
What is your use case(s), might I ask? Prevention of array stomping,
I thought, had a net positive effect on performance, because it no
longer has to lock the GC for thread-local appends.
I would guess they're setting length to zero and appending to re-use
the memory.
Exactly. So far looks like upon transition to D2 almost all arrays
used in our code will need to be replaced with some variation of
Appender!T
I think you might find that it will run considerably faster in that
case. In the old mechanism of D1, the GC lock was used on every append,
and if you had multiple threads appending simultaneously, they were
contending with the single element cache to look up block info.
Appender only needs to look up GC block info when it needs more memory
from the GC.
We don't use threads.
In that case, the GC will not use a lock (I think it avoids allocating a
lock until at least 2 threads exist). However, you can still benefit from
the expanded cache if you are appending to 2 to 8 arrays simultaneously.
The D1 cache was for one block only.
-Steve
