> This patch is the real fix for strings with the BUFFER_external_FLAG. > It requires the previous dod.c and resources.c patches to be applied. > > Strings marked with the BUFFER_external_FLAG point to the external > memory rather than making a copy for themselves. Side effects of this > are (1) less memory usage, (2) external updates to the string are > reflected in the Parrot STRING (except for length changes!), and (3) > these strings are skipped over when memory is getting moved around > during a compaction.
Fixing BUFFER_external_FLAG is probably a good thing, and I'm up for applying them after 008 goes out the door. However, BUFFER_external_FLAG and BUFFER_selfpoolptr_FLAG almost seem to have complementary purposes now. (The latter was something that I introduced along with the current COW version.) selfpoolptr indicates that the header references memory in the local pool. This allows a non-constant-header string to point cowingly towards a constant buffer in the constant pool. The selfpoolptr flag would be false, and it would avoid collecting/copying/destroying the data. This is rather similar in nature to external's behavior, and I imagine we could either: a) make them act identically, like this patch does b) just have people who want external data to unset selfpoolptr. Thoughts? Mike Lambert
