I tried yesterday to apply the patch to my sqlite3.c and I think that the problem's not fixed: but perhaps I'm wrong or I miss something applying the patch. Can you provide me a sqlite3.c source with this patch applied correctly so I can test if this issue is correct?
Il 10/09/2010 10.53, Dan Kennedy ha scritto: >> Michele, thanks for pointing out to vmmap, sysinternals made them so >> fast, I >> can not track them all. This is an excellent utility. >> I think that the development team already knows that is going on, >> just my >> speculation. >> >> As long as I see, every next file mapping wants to see not only >> requested >> 32k region, but also every prior, so every CreateFileMapping/ >> MapViewOfFile >> wants more on every next step, 32k-64k-96k (this is visible in vmmap >> and >> corresponds to the code in winShmMap). And as long as I see, the >> problem is >> that Windows allocates separated ranges of memory space for every >> region >> even if they're intersecting, i.e every MapViewOfFile needs to find >> a brand >> new address space range for every new region request. So we have >> >> 2,000,000k = (32k*(X + 1)/2)*X >> >> where X - is the number of region requests when the memory address >> space get >> to 2g limit. >> And the answer for this X here is about 350 that leads us to 350*32k >> = 11M >> shm file. So this size that I noticed in my tests confirms this theory > This bug analysis is correct. > > The bug is fixed by Shane's patch linked earlier in the thread. With > the patch, an 11MB -shm file is mapped into memory in around 350 chunks > with an average size of 48KB. Total address space used is around > (350*48KB). > Instead of the (350*5.5MB) that 3.7.2 was using. > >> I don't know about the internal logic that requires this, but on >> Windows 350 >> regions is a maximum in this case. Does it mean that linux share >> address >> space for superset/subset regions in contrary to Windows logic? > It is separate. This bug was in the OS specific win32 layer > > Dan. > > > > > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > -- Selea s.r.l. Michele Pradella R&D SELEA s.r.l. Via Aldo Moro 69 Italy - 46019 Cicognara (MN) Tel +39 0375 889091 Fax +39 0375 889080 *michele.prade...@selea.com* <mailto:michele.prade...@selea.com> *http://www.selea.com* _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
