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From Michael Malone <mjmal...@gmail.com>
Subject Re: Standardizing Timestamps Across Clients
Date Thu, 18 Mar 2010 20:20:34 GMT
A standard default would be nice, but while we're making  
recommendations I'd also suggest that client libs should make this  
parameter easy to override. Client apps can do lots of interesting  
things by setting timestamps explicitly. You can get a sort of quasi- 
transaction by using the same timestamp for a set of operations, for  
example.

Mike

On Mar 18, 2010, at 1:11 PM, Ben Standefer <benstandefer@gmail.com>  
wrote:

> +1 I think this is a great idea.  I've been bitten by this when  
> switching
> clients, and it took a while to figure out what was going on.  Good  
> job on
> pycassa, vomjom!
>
> -Ben
>
>
> 2010/3/18 Ted Zlatanov <tzz@lifelogs.com>
>
>> On Thu, 18 Mar 2010 02:36:35 -0500 Jonathan Hseu <vomjom@vomjom.net>
>> wrote:
>>
>> JH> Jonathan Ellis suggested that I bring this issue to the dev  
>> mailing
>> list:
>> JH> Cassandra should recommended a default timestamp across all  
>> clients
>> JH> libraries.
>> ...
>> JH> Here's what different clients are using:
>>
>> JH> 1. Cassandra CLI: Milliseconds since UTC epoch.
>> JH> 2. lazyboy: Seconds since UTC epoch.  It used to be seconds  
>> since local
>> time
>> JH> epoch.  Now it's changing again to microseconds since UTC epoch.
>> JH> 3. driftx's client: Milliseconds since UTC epoch.
>> JH> 4. The example app, Twissandra: Microseconds since UTC epoch.
>> JH> 5. pycassa: Microseconds since UTC epoch.  It used to be  
>> seconds since
>> local
>> JH> time epoch.
>> JH> 6. The most popular Cassandra Ruby client: Microseconds since UTC
>> epoch.
>>
>> It's good to standardize :)
>>
>> In Perl land, Net::Cassandra::Easy is using seconds but should be  
>> using
>> microseconds.  I'll change it for 0.4 (the underlying Thrift code  
>> will
>> DTRT for the 64-bit encoding using Bit::Vector).  Net::Cassandra uses
>> seconds and should also be changed; CC-d to that module's maintainer.
>>
>> Ted
>>
>>

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