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From William Slacum <wsla...@gmail.com>
Subject Re: delete + insert case
Date Thu, 17 Mar 2016 15:40:18 GMT
Be aware of the OS's underlying granularity for time as well:

http://docs.oracle.com/javase/6/docs/api/java/lang/System.html#currentTimeMillis%28%29

I almost wonder if it's better to use the RowDeletingIterator in this case.
If the check it does is "if TS < delete marker TS", in theory you could get
away with putting the delete marker inside the same Mutation as the update
and the iterator will mask any data marked with a TS before the delete
marker.

On Thu, Mar 17, 2016 at 11:18 AM, Josh Elser <josh.elser@gmail.com> wrote:

> Server-assigned timestamps aren't noticeably slower than user-assigned
> timestamps, if that's what you're referring to WRT throughput.
>
> As for using currentTimeMillis(), probably fine, but not always.
>
> 1) NTP updates might cause currentTimeMillis() to change in reverse
> 2) You need to make sure the delete and update always come from the same
> host (otherwise two hosts might have different values for
> currentTimeMillis())
>
> Time is hard in distributed systems.
>
>
> z11373 wrote:
>
>> Thanks Josh! For better throughput, I think I'd just assign the timestamp
>> from my code.
>> Using this code, System.currentTimeMillis(); for timestamp should be ok,
>> right?
>>
>>
>> Thanks,
>> Z
>>
>>
>>
>>
>> --
>> View this message in context:
>> http://apache-accumulo.1065345.n5.nabble.com/delete-insert-case-tp16375p16382.html
>> Sent from the Developers mailing list archive at Nabble.com.
>>
>

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