From 9c832964b9002b1754d8cca590e7fcc2498239a1 Mon Sep 17 00:00:00 2001 From: Anne van Kesteren Date: Wed, 8 Jul 2020 20:03:36 +0200 Subject: [PATCH] Quota is not supposed to be a function of available space Also make it clear usage and quota for storage shelves are ultimately implementation-defined. Helps with #95 and #70. Closes #106. --- storage.bs | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/storage.bs b/storage.bs index c989039..cdfbe3c 100644 --- a/storage.bs +++ b/storage.bs @@ -471,20 +471,26 @@ locally.

Usage and quota

-

The storage usage of a storage shelf is a rough estimate of the amount -of bytes used by it. +

The storage usage of a storage shelf is an implementation-defined +rough estimate of the amount of bytes used by it.

This cannot be an exact amount as user agents might, and are encouraged to, use deduplication, compression, and other techniques that obscure exactly how much bytes a storage shelf uses. -

The storage quota of a storage shelf is a conservative estimate of the -total amount of bytes it can hold. This amount should be less than the total available storage space -on the device to give users some wiggle room. +

The storage quota of a storage shelf is an +implementation-defined conservative estimate of the total amount of bytes it can hold. This +amount should be less than the total storage space on the device. It must not be a function of the +available storage space on the device. -

User agents are strongly encouraged to consider navigation frequency, recency of -visits, bookmarking, and permission for {{"persistent-storage"}} when -evaluating quotas. +

+

User agents are strongly encouraged to consider navigation frequency, recency of visits, + bookmarking, and permission for {{"persistent-storage"}} when + determining quotas. + +

Directly or indirectly revealing available storage space can lead to fingerprinting and leaking + information outside the scope of the origin involved. +