For memory efficiency in content processes, we need to be able to store
changed preferences in a separate dynamic hashtable when their values don't
match the snapshot values.
That makes iteration over the full set of preferences somewhat more
complicated, since not only do we need to iterate over two tables, but we also
need to ignore preferences in the snapshot table if they also exist in the
dynamic hashtable.
This patch solves that problem by adding an iterator helper which iterates
over values in both tables, and skips values in the static table if they also
exist in the dynamic table.
In order to support completely deleting preferences that exist in the base
table, it also ignores all dynamic entries with the None type, so that they
can completely mask deleted base table values.
MozReview-Commit-ID: LCIwyPJMByj
--HG--
extra : intermediate-source : f9362cf1add47c2f62529e42764ed6088d274170
extra : absorb_source : fdaf890e85af43271cffd2371cf6fbf408c6cc50
extra : source : d344247b870668f53fa645e72bda4bb4309346c8
extra : histedit_source : 6cd565727eff617eeba386b563477ce4d4bfbd0a
This is based on the SharedStringMap that's currently used for shared memory
string bundles.
When the parent process is ready to launch its first content process, it
creates a snapshot of the current state of the preference database, maps that
as read-only, and shares it with each content process. Look-ups in the
snapshotted map are done entirely using data in the shared memory region. It
doesn't require any additional per-process state data.
MozReview-Commit-ID: BdTUhak7dmS
--HG--
extra : intermediate-source : 434106f1b75e3ba900912f261bd22a1b7f5c931d
extra : absorb_source : 647ad37590448ad3c1eb8eb512bf671f262fa96e
extra : source : 68bb03c63b3cee1d47cbddfd3abf919f5783c04b
extra : histedit_source : 2228a9f8395929f5072a3c5ebda6ae3221e4a62d
For memory efficiency in content processes, we need to be able to store
changed preferences in a separate dynamic hashtable when their values don't
match the snapshot values.
That makes iteration over the full set of preferences somewhat more
complicated, since not only do we need to iterate over two tables, but we also
need to ignore preferences in the snapshot table if they also exist in the
dynamic hashtable.
This patch solves that problem by adding an iterator helper which iterates
over values in both tables, and skips values in the static table if they also
exist in the dynamic table.
In order to support completely deleting preferences that exist in the base
table, it also ignores all dynamic entries with the None type, so that they
can completely mask deleted base table values.
MozReview-Commit-ID: LCIwyPJMByj
--HG--
extra : source : d344247b870668f53fa645e72bda4bb4309346c8
extra : histedit_source : bb670afc815f3953ccadebddd04962836569b281
This is based on the SharedStringMap that's currently used for shared memory
string bundles.
When the parent process is ready to launch its first content process, it
creates a snapshot of the current state of the preference database, maps that
as read-only, and shares it with each content process. Look-ups in the
snapshotted map are done entirely using data in the shared memory region. It
doesn't require any additional per-process state data.
MozReview-Commit-ID: BdTUhak7dmS
--HG--
extra : source : 68bb03c63b3cee1d47cbddfd3abf919f5783c04b
For memory efficiency in content processes, we need to be able to store
changed preferences in a separate dynamic hashtable when their values don't
match the snapshot values.
That makes iteration over the full set of preferences somewhat more
complicated, since not only do we need to iterate over two tables, but we also
need to ignore preferences in the snapshot table if they also exist in the
dynamic hashtable.
This patch solves that problem by adding an iterator helper which iterates
over values in both tables, and skips values in the static table if they also
exist in the dynamic table.
In order to support completely deleting preferences that exist in the base
table, it also ignores all dynamic entries with the None type, so that they
can completely mask deleted base table values.
MozReview-Commit-ID: LCIwyPJMByj
--HG--
extra : rebase_source : 833abea0620f75410f9922e5d4b5cf36b84e9e50
extra : absorb_source : 89690c674120eb99ad25804408b1c3864c7b1fc8
This is based on the SharedStringMap that's currently used for shared memory
string bundles.
When the parent process is ready to launch its first content process, it
creates a snapshot of the current state of the preference database, maps that
as read-only, and shares it with each content process. Look-ups in the
snapshotted map are done entirely using data in the shared memory region. It
doesn't require any additional per-process state data.
MozReview-Commit-ID: BdTUhak7dmS
--HG--
extra : rebase_source : e7cb96dd52380f2ed2fbd79b4e157e4efab65cb0
extra : absorb_source : ed95ed85388875353458eb65e41727e606ebf097
