gldownload: don't pre-allocate ion buffers
NXP's gldownload fastpath requests 3 ION buffers to be created in the
pool without any upper bound. That means 3 buffers are allocated the
moment the pool is activated and there's no upper bound on how many
the pool can allocate.
This is an issue when working with larger buffers as we can easily
run out of CMA memory. The cost of allocating an ION buffer when
needed is negligible. glupload for example doesn't even use a pool.
Since gldownload is using a pool the already negligible cost is
hidden further.
In most common cases (i.e. downstream doesn't hold on to downloaded
buffers) this change results in only one buffer being allocated.
For a 1080p YUY -> RGBA conversion that's downloaded that's a
CMA savings of ~16 MB. For downstream elements that hold on to buffers
(e.g. certain double buffered sinks) more buffers will be allocated as
needed, up to 3 to prevent OOM.
Change-Id: I68172d7e9d1bf634900cb639f90843768ac525ae
diff --git a/ext/gl/gstgldownloadelement.c b/ext/gl/gstgldownloadelement.c
index 77dfc46..8b4ea4b 100644
--- a/ext/gl/gstgldownloadelement.c
+++ b/ext/gl/gstgldownloadelement.c
@@ -567,8 +567,8 @@
GST_DEBUG_OBJECT (download, "create pool %p", pool);
- //propose 3 buffers for better performance
- gst_query_add_allocation_pool (query, pool, size, 3, 0);
+ /* propose up to 3 buffers with no minimum to save memory */
+ gst_query_add_allocation_pool (query, pool, size, 0, 3);
gst_object_unref (pool);
