Commit e777adf

nsxive777adf

Allow setting cache size based on memory percentage (#184)

The problem:

1. For the most people imlib2's default 4MiB is unreasonably low;

2. Hardcoding cache size to ~256MiB has performance benefits and doesn't
   increase RAM usage too much on relatively modern systems;

3. But we can't do that, because that would be detrimental to low spec systems
   that (apparently) not (?) building nsxiv from source, as been discussed
   #171

Solution:

Calculate cache size based on total memory.

Default is set as 3%, which means:
* ~245MiB for 8GiB
* ~30MiB for 1GiB
* and so on

CACHE_SIZE_LIMIT (256MiB by default) sets the highest possible value. And in
case we cannot determine the total memory (e.g since _SC_PHYS_PAGES isn't
POSIX) use CACHE_SIZE_FALLBACK (32MiB by default) instead.

Author: MahouShoujoMivutilde
Date: 2022-01-01 11:55 +0300
Committer: GitHub · 2022-01-01 14:55 +0600
Parent: 1a691d4
Commit: e777adf98534394ca005a1ca541696b06c791aa6

+26 −5

2 files changed

Browse files Patch

−Context 3+

M config.def.h +7 −4
M image.c +19 −1

M config.def.h View

M image.c View

		@@ -62,11 +62,14 @@ static const bool ANTI_ALIAS = true;
62	62		*/
63	63		static const bool ALPHA_LAYER = false;
64	64
65		−	/* cache size for imlib2, in bytes. For backwards compatibility reasons, the
66		−	* size is kept at 4MiB. For most users, it is advised to pick a value close to
67		−	* or above 128MiB for better image (re)loading performance.
	65	+	/* percentage of memory to use for imlib2's cache size.
	66	+	* 3 means use 3% of total memory which is about 245MiB on 8GiB machine.
	67	+	* 0 or less means disable cache.
	68	+	* 100 means use all available memory (but not above CACHE_SIZE_LIMIT).
68	69		*/
69		−	static const int CACHE_SIZE = 4 * 1024 * 1024; /* 4MiB */
	70	+	static const int CACHE_SIZE_MEM_PERCENTAGE = 3; /* use 3% of total memory for cache */
	71	+	static const int CACHE_SIZE_LIMIT = 256 * 1024 * 1024; /* but not above 256MiB */
	72	+	static const int CACHE_SIZE_FALLBACK = 32 * 1024 * 1024; /* fallback to 32MiB if we can't determine total memory */
70	73
71	74		#endif
72	75		#ifdef _THUMBS_CONFIG

		@@ -46,12 +46,30 @@ enum { DEF_WEBP_DELAY = 75 };
46	46		#define ZOOM_MIN (zoom_levels[0] / 100)
47	47		#define ZOOM_MAX (zoom_levels[ARRLEN(zoom_levels)-1] / 100)
48	48
	49	+	static int calc_cache_size(void)
	50	+	{
	51	+	int cache;
	52	+	long pages, page_size;
	53	+
	54	+	if (CACHE_SIZE_MEM_PERCENTAGE <= 0)
	55	+	return 0;
	56	+
	57	+	pages = sysconf(_SC_PHYS_PAGES);
	58	+	page_size = sysconf(_SC_PAGE_SIZE);
	59	+	if (pages < 0 \|\| page_size < 0)
	60	+	return CACHE_SIZE_FALLBACK;
	61	+	cache = (pages/100) * CACHE_SIZE_MEM_PERCENTAGE;
	62	+	cache *= page_size;
	63	+
	64	+	return MIN(cache, CACHE_SIZE_LIMIT);
	65	+	}
	66	+
49	67		void img_init(img_t img, win_t win)
50	68		{
51	69		imlib_context_set_display(win->env.dpy);
52	70		imlib_context_set_visual(win->env.vis);
53	71		imlib_context_set_colormap(win->env.cmap);
54		−	imlib_set_cache_size(CACHE_SIZE);
	72	+	imlib_set_cache_size(calc_cache_size());
55	73
56	74		img->im = NULL;
57	75		img->win = win;

nsxiv/e777adf

Allow setting cache size based on memory percentage (#184)

nsxive777adf