Re: lock statement questions

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Greg Young wrote:

<snip>

Jon Skeet
It also fails as soon as you've got a property which needs to set two
different variables. I prefer to have just one way of obtaining thread-
safety: a lock.

As I had said, I was dealing with a case where we were dealing with
something under reference size (without screwing with alignment etc). I feel
removing the needless locking is important in performant areas of code.

How often have you come across code where the locking was the
performance hit? I've only done so *once* - and that was when writing
lock primitives myself.

I'll take the balance of consistency (only needing one way of achieving
thread safety) over a *possible* performance hit until that performance
hit is *proven* to be a bottleneck. I believe the number of
applications where it's an issue is vanishingly small.

Just to be clear .. I agree that volatility is a valid concern; I just think
that using lock to provide it is bad practice as it comes with significant
overhead (in the range of 100 times slower) and works as a by product of the
optimizer not inlining (see previous post for inlining)

I believe in simplicity/consistency over performance - it's easier to
refactor to performance than the other way round. I'm a *big* fan of
not micro-optimising.

Jon

.

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