"Tom Lane" <[EMAIL PROTECTED]> writes: > Gregory Stark <[EMAIL PROTECTED]> writes: >> What did you think about protecting against torn writes using id numbers >> every >> 512 bytes. > > Pretty much not happening; or are you volunteering to fix every part of > the system to tolerate injections of inserted data anywhere in a stored > datum?
I was thinking to do it at a low level as the xlog records are prepared to be written to the filesystem and as the data is being read from disk. I haven't read that code yet to see where to inject it but I understand there's already a copy happening and it could be done there. Even if we optimize out all the copies we could do it in the actual i/o call using readv/writev. I wasn't thinking of doing it on actual disk buffers since it doesn't help us avoid full page writes, but it could be done there too using readv/writev in the smgr. That might be useful for a full_page_writes=off system so even if it can't guarantee no corruption at least it can guarantee no silent corruption. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
