On 2017/05/09 23:21:33 +0800, Junchang Wang wrote:
> Hi Akira,
>
> That's the major point. Fair enough :-)
>
So, are you OK with me submitting the patch with your Acked-by?
Thanks, Akira
>
> Thanks,
> --Jason
>
>
> On Tue, May 9, 2017 at 10:56 PM, Akira Yokosawa <akiyks@xxxxxxxxx> wrote:
>> On 2017/05/09 16:48:12 +0800, Junchang Wang wrote:
>>> Oops. Forgot the summary in previous email. Resend the patch.
>>>
>>>
>>> The Answer to Quick Quiz 5.27 is a bit hard to follow. Rewrite it.
>>>
>>> Signed-off-by: Junchang Wang <junchangwang@xxxxxxxxx>
>>> ---
>>> count/count.tex | 14 +++++++-------
>>> 1 file changed, 7 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/count/count.tex b/count/count.tex
>>> index cc47554..6dfc7a6 100644
>>> --- a/count/count.tex
>>> +++ b/count/count.tex
>>> @@ -1258,13 +1258,13 @@ machine.
>>> fast and scalable while allowing readers to also enjoy
>>> reasonable performance and scalability?
>>> \QuickQuizAnswer{
>>> - One approach would be to maintain a global approximation
>>> - to the value.
>>> - Readers would increment their per-thread variable, but when it
>>> - reached some predefined limit, atomically add it to a global
>>> - variable, then zero their per-thread variable.
>>> - This would permit a tradeoff between average increment overhead
>>> - and accuracy of the value read out.
>>> + One approach would be to add a global variable maintaining a
>>> + approximation to the exact value. An updater would increment its
>>> + per-thread variable, and when its value reaches predefined limit,
>>> + atomically add the value to the global variable, then zero its
>>> + per-thread variable. Readers simply return the value of global variable,
>>> + enjoying reasonable performance. This would permit a tradeoff between
>>> + average increment overhead and accuracy of the value read out.
>>>
>>> The reader is encouraged to think up and try out other approaches,
>>> for example, using a combining tree.
>>>
>>
>> Hi Junchang,
>>
>> What confused you seems to be a simple typo.
>> Isn't the following one-liner sufficient for you?
>>
>> Thanks, Akira
>>
>> --8<---->8--
>> From 725b32938e0cbc245e5a528fd475951bb8be1de5 Mon Sep 17 00:00:00 2001
>> From: Akira Yokosawa <akiyks@xxxxxxxxx>
>> Date: Tue, 9 May 2017 23:39:57 +0900
>> Subject: [PATCH] count: Fix typo in Answer to Quick Quiz 5.27
>>
>> Reported-by: Junchang Wang <junchangwang@xxxxxxxxx>
>> Signed-off-by: Akira Yokosawa <akiyks@xxxxxxxxx>
>> ---
>> count/count.tex | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/count/count.tex b/count/count.tex
>> index cc47554..096b53d 100644
>> --- a/count/count.tex
>> +++ b/count/count.tex
>> @@ -1260,7 +1260,7 @@ machine.
>> \QuickQuizAnswer{
>> One approach would be to maintain a global approximation
>> to the value.
>> - Readers would increment their per-thread variable, but when it
>> + Updaters would increment their per-thread variable, but when it
>> reached some predefined limit, atomically add it to a global
>> variable, then zero their per-thread variable.
>> This would permit a tradeoff between average increment overhead
>> --
>> 2.7.4
>>
>>
>
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