RE: Ants Data Server

  • From: "Laimutis Nedzinskas" <Laimutis.Nedzinskas@xxxxxxxxxxxxx>
  • To: <oracle-l@xxxxxxxxxxxxx>
  • Date: Tue, 19 Sep 2006 16:05:12 -0000

There are no miracles in this world.  
A few quotes from :

PBXT is transactional, but only writes data once namely, to the log.
This has a number of consequences:
* Firstly the obvious: writing less, saves times.
* The database table data actually resides in the logs (how we get to
the table data is explained below in the section "Getting a Handle on
the Problem").
* Since table data is not stored in any particular table file, the size
of a table is unlimited.
* Since log files are written sequentially, PBXT only ever writes
transaction data sequentially.
* Since data is only written sequentially, variable sized rows pose no
problem to PBXT. In fact, there is actually no need to specify a maximum
size for column types such as VARCHAR, VARBIN or BLOBs.
* Since log file data is written immediately, records in the cache are
never "dirty" (i.e. must be flushed before being freed). This greatly
speeds up and simplifies cache management.
* Since log files are never updated, PBXT never modifies table data in
place. This means that instead of updating a record, PBXT writes a new
* Since database table data is never updated rollback never has to undo
a change.
* Since data is never overwritten, the internal data structure is
inherently more stable than a standard implementation.
PBXT takes this idea a step further. In a standard implementation one
transaction log is used. To reduce contention in a high concurrency
environment, PBXT uses one log per thread of execution. This effectively
means each transaction has its own log.


-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx
[mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Remigiusz Sokolowski
Sent: 19. september 2006 15:50
To: Roger.Xu@xxxxxxxxxxx
Cc: Oracle-L@Freelists. Org (E-mail)
Subject: Re: Ants Data Server

Roger Xu wrote:

> They claim there is rarely write-locks rows and all indexes, queues 
> and other internal datastructures are fully concurrent, with no lock 
> waiting ever!
> How is this possible?
>     -----Original Message-----
>     *From:* oracle-l-bounce@xxxxxxxxxxxxx
>     [mailto:oracle-l-bounce@xxxxxxxxxxxxx]*On Behalf Of *Roger Xu
>     *Sent:* Monday, September 18, 2006 10:05 AM
>     *To:* Oracle-L@Freelists. Org (E-mail)
>     *Subject:* OT: Ants Data Server
>     Hi List,  
>     Anyone has experience with Ants Data Server?
>     Roger Xu
well, I suppose it can be done in similar way as it is in case of under link above You'll find engine for
mysql, which author claims to run without locks, while being


Remigiusz Sokolowski <rems@xxxxxxxx>
WP/PTI/DIP/ZAB (+04858) 52 15 770



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