Hello, Vlad! Tuesday, April 3, 2012, 1:18:05 PM, you wrote:
>> - not all db pages need to be encrypted. for example PIP, TIP, etc. >> Performance effect of decrypting/encrypting these pages can be >> disasterous. VK> Where it conflicts with my proposition ? wrote just for the case. VK> a) There is no checksum field in ODS12, oops. VK> but it doesn't matter here because VK> even if will return checksums it should be calculated for encrypted image VK> *stored on disk* (because checksums are guard against disk errors). I meant 12345 checksum that was fixed since InterBase 5. So, page checksums are not "guards" of the pages for a long time. They are just indicators, that if there no 12345, page can be considered as crap. VK> b) Page header sooner af all will not be encrypted. VK> How do you going to detect still not encrypted pages if you against VK> "encrypted" flag ? Well, I'd better look about it in IB, and then tell more. >> Pages itself does not need that flags - they are being written >> in atomic way, so they can't be "in progress". VK> This flag is *required* to distinguish encrypted pages. I don't understand VK> why do you object it. Because I consider decryption as a "single-user" operation. Seems you want people to work with DB while it is being encrypted. >> Yes, this way FB will read (at least) the whole database. >> So? It was intended to do it when encryption/decryption was started. VK> Why do we need to do a dumb work ? let this dumb work done once, than do it each time reading the page. -- Dmitry Kuzmenko, www.ibase.ru, (495) 953-13-34 ------------------------------------------------------------------------------ Better than sec? Nothing is better than sec when it comes to monitoring Big Data applications. Try Boundary one-second resolution app monitoring today. Free. http://p.sf.net/sfu/Boundary-dev2dev Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
