X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fcompress_parallel.c;h=eeb9f6f242dbcd2575dc983e2477e6955e94071b;hb=882dc6e5dece7f521b9de6c4337aad0411ed00da;hp=fa7f5dde113750adea8a1b43f12227748cd5109d;hpb=4263fdbc0599a27356b6afb9e6bf6daf786c1363;p=wimlib

diff --git a/src/compress_parallel.c b/src/compress_parallel.c
index fa7f5dde..eeb9f6f2 100644
--- a/src/compress_parallel.c
+++ b/src/compress_parallel.c
@@ -43,6 +43,9 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#ifdef HAVE_SYS_SYSCTL_H
+#  include <sys/sysctl.h>
+#endif
 
 struct message_queue {
 	struct list_head list;
@@ -116,12 +119,19 @@ get_avail_memory(void)
 	if (phys_bytes == 0)
 		goto default_size;
 	return phys_bytes;
-#else
+#elif defined(_SC_PAGESIZE) && defined(_SC_PHYS_PAGES)
 	long page_size = sysconf(_SC_PAGESIZE);
 	long num_pages = sysconf(_SC_PHYS_PAGES);
 	if (page_size <= 0 || num_pages <= 0)
 		goto default_size;
 	return ((u64)page_size * (u64)num_pages);
+#else
+	int mib[2] = {CTL_HW, HW_MEMSIZE};
+	u64 memsize;
+	size_t len = sizeof(memsize);
+	if (sysctl(mib, ARRAY_LEN(mib), &memsize, &len, NULL, 0) < 0 || len != 8)
+		goto default_size;
+	return memsize;
 #endif
 
 default_size:
@@ -423,16 +433,26 @@ new_parallel_chunk_compressor(int out_ctype, u32 out_chunk_size,
 
 	desired_num_threads = num_threads;
 
-	chunks_per_msg = MAX_CHUNKS_PER_MSG;
-	msgs_per_thread = 2;
+	if (out_chunk_size < ((u32)1 << 23)) {
+		chunks_per_msg = MAX_CHUNKS_PER_MSG;
+		msgs_per_thread = 2;
+	} else {
+		/* Big chunks: Just have one buffer per thread --- more would
+		 * just waste memory.  */
+		chunks_per_msg = 1;
+		msgs_per_thread = 1;
+	}
 	for (;;) {
 		approx_mem_required =
 			(u64)chunks_per_msg *
 			(u64)msgs_per_thread *
 			(u64)num_threads *
 			(u64)out_chunk_size
+			+ out_chunk_size
 			+ 1000000
-			+ (out_chunk_size * num_threads * 4);
+			+ num_threads * wimlib_get_compressor_needed_memory(out_ctype,
+									    out_chunk_size,
+									    NULL);
 		if (approx_mem_required <= max_memory)
 			break;