Op 01-03-11 09:17, Shane Hathaway schreef: > On 02/28/2011 07:37 PM, Shane Hathaway wrote: >> On 02/28/2011 08:19 AM, Maurits van Rees wrote: >>> I wonder if there is some code that mistakenly throws away the wrong >>> blob; it should throw away the oldest one I'd think, and not the one >>> that it just loaded. >>> >>> The workaround is probably just to not set the blob-cache-size this low. >>> But I tried this low setting to work around a different problem, which >>> I will report in a different post. >> >> This reveals how naive the blob cache management is in both RelStorage >> and ZEO. It is smart enough to use the atime of files (thus you should >> not disable atime on a filesystem that hosts a blob cache), but the >> cache management does not guarantee downloaded files are kept long >> enough to actually read them. > > Oops, I take it back after reviewing the blob code tonight. ZODB 3.9 > and above is not naive about this issue. While ZODB 3.8 allows blob > files to disappear at the wrong times, ZODB 3.9 has internal retry > mechanisms that ensure blob files will be opened even when the blob > cache size is too small. > > RelStorage can not fix this issue. If you want stable blob support, as > Hanno said, you need ZODB 3.9 or above.
Not an option for the short term, as we are still on Plone 3, but good to know, thanks. -- Maurits van Rees Web App Programmer at Zest Software: http://zestsoftware.nl Personal website: http://maurits.vanrees.org/ _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
