tree 2925a45e91f235ebe6b8413191d7cf5ddda44dda
parent f6566314f84feaf7906fe89ac9cab694dfd75451
author fmalita <fmalita@chromium.org> 1475267659 -0700
committer Commit bot <commit-bot@chromium.org> 1475267659 -0700

Add a SkRWBuffer reserve mechanism

Currently, Chromium stores segmented data in a SharedBuffer and appends
to SkRWBuffer one segment at a time:

        const char* segment = 0;
        for (size_t length = data->getSomeData(segment, m_rwBuffer->size());
            length; length = data->getSomeData(segment, m_rwBuffer->size())) {
            m_rwBuffer->append(segment, length, remaining);
        }

This can yield a bunch of just-above-4k allocations => wasted RAM due to
internal fragmentation.

Ideally, we'd want a SkRWBuffer::reserve(size_t bytes) API, but the
current internals don't support that trivially.

Alternatively, the caller can pass a reserve hint at append() time.

BUG=chromium:651698
R=scroggo@google.com,reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2385803002

Review-Url: https://codereview.chromium.org/2385803002