couchdb-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jan Lehnardt <...@apache.org>
Subject Re: Why sequential document ids? [was: Re: What's the speed(performance) of couchdb?]
Date Mon, 02 Mar 2009 18:37:36 GMT

On 2 Mar 2009, at 19:29, Damien Katz wrote:

>
> On Mar 2, 2009, at 1:22 PM, Jan Lehnardt wrote:
>
>>
>> On 2 Mar 2009, at 19:17, Brian Candler wrote:
>>
>>> On Fri, Feb 27, 2009 at 10:11:12AM -0800, Chris Anderson wrote:
>>>> I wonder if there's a way to get roughly ascending uuids (v1-ish)
>>>> without the security issues that come from having the originating  
>>>> node
>>>> permanently inscribed on each document...
>>>
>>> If doing bulk inserts: the client can ask for a uuid, take the top  
>>> N bits,
>>> and append its own M-bit sequence number to the end?
>>
>> it can also get document-count UUIDs sort them and bulk insert docs
>> in that order. :)
>
> That won't help because the insertions places in the btree are still  
> evenly distributed, and besides CouchDB does that step itself.
>
> A better way would be to grab a UUID and increment it by 1 for the  
> id of each new document you are saving. You still don't get great  
> caching behavior as you are still inserting into a random place in  
> the btree, but it's much better than N random inserts.

right, I only read the first half of your earlier remark: "And they  
don't need to sort higher or lower than all the other ids, so long as  
they are clustered together. "

nevermind.

Cheers
Jan
--



Mime
View raw message