On Fri, 13 Mar 2009, Pierre Chatelier might have said: > Hello, > > I am using SQLITE to store and retrieve raw data blocks that are > basically ~300Ko. Each block has an int identifier, so that insert/ > select are easy. This is a very basic use : I do not use complex > queries. Only "INSERT/SELECT where index=..." > > Now, I am thinking about performance, for writing a sequence of a few > hundreds 300k blocks, as fast as possible. > Obviously, I use bind_blob(), blob_read() and blob_write() functions. > I have already tuned the PRAGMAs for journal/synchronous/page_size/ > cache, so that it's rather efficient. > I do not DELETE any content and the whole database is dropped after > use: VACUUM is not important. > > There are other ways to optimize, but I wonder if it is worth, or it > the gain would be only marginal regarding what I am doing. > 1)recompile SQLite ? Which compile options would help in this case ? > 2)using other memory allocators ? I am not sure that writing big data > blocks triggers many calls to malloc() > 3)using compression ? zlib could help, but since my data does not > compress very well (Let's say an average 20% space can be saved per > block), I am not sure that the compression time will balance the > writing time. > > Of course, I am only asking for advices regarding your experience, > there is certainly no exact answer, and it will always depend on my > data. > > Regards, > > Pierre Chatelier
Why do you not use the int converted to a hex (sprintf("%08x", id)) as a file name and just use the file system? Mike _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users