X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fcompress_parallel.c;h=376e59d6a2fdca8a05fae9486d58fc0f51bba08d;hb=e074c6d474920b8bc1436f105e0dff89e6a4bccb;hp=d0ce5266464cb4021797cbd2a81c4ed5c5c652c3;hpb=883833a4b3dabec325edf1ca938000f91d587c00;p=wimlib

diff --git a/src/compress_parallel.c b/src/compress_parallel.c
index d0ce5266..376e59d6 100644
--- a/src/compress_parallel.c
+++ b/src/compress_parallel.c
@@ -26,6 +26,8 @@
 #  include "config.h"
 #endif
 
+#ifdef ENABLE_MULTITHREADED_COMPRESSION
+
 #include "wimlib/assert.h"
 #include "wimlib/chunk_compressor.h"
 #include "wimlib/error.h"
@@ -421,16 +423,26 @@ 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;
 
@@ -534,3 +546,5 @@ err:
 	parallel_chunk_compressor_destroy(&ctx->base);
 	return ret;
 }
+
+#endif /* ENABLE_MULTITHREADED_COMPRESSION */