[ZODB-Dev] ZEO packing

[Toby Dickenson]

A few weeks ago Jeremy added SlowMethodThread handling to the ZEO 2=20
StorageServer so that potentially long undo operations dont block other Z=
EO=20
clients. This is *very* nice.

This new mechanism has also been used for handling pack, which has caused=
 a=20
change in behavior that I was not expecting. Previously ZEO clients would=
 see=20
the pack method return immediately, and the ZEO server ran the pack=20
asynchronously. Today the packing will block that ZEO client, the same as=
 if=20
there was no ZEO between the client and the underlying storage.

I think this new behaviour is better, but I guess it could cause a proble=
m if=20
you are not expecting it.