--- a/memory/jemalloc/jemalloc.c
+++ b/memory/jemalloc/jemalloc.c
@@ -169,17 +169,17 @@
    /*
     * MALLOC_PAGEFILE causes all mmap()ed memory to be backed by temporary
     * files, so that if a chunk is mapped, it is guaranteed to be swappable.
     * This avoids asynchronous OOM failures that are due to VM over-commit.
     *
     * XXX OS X over-commits, so we should probably use mmap() instead of
     * vm_allocate(), so that MALLOC_PAGEFILE works.
     */
-#  define MALLOC_PAGEFILE
+//#  define MALLOC_PAGEFILE
 #endif
 
 #ifdef MALLOC_PAGEFILE
 /* Write size when initializing a page file. */
 #  define MALLOC_PAGEFILE_WRITE_SIZE 512
 #endif
 
 #ifdef MOZ_MEMORY_LINUX
@@ -5094,18 +5094,19 @@ malloc_ncpus(void)
 #elif (defined(MOZ_MEMORY_LINUX))
 #include <fcntl.h>
 
 static inline unsigned
 malloc_ncpus(void)
 {
 	unsigned ret;
 	int fd, nread, column;
-	char buf[1];
+	char buf[1024];
 	static const char matchstr[] = "processor\t:";
+	int i;
 
 	/*
 	 * sysconf(3) would be the preferred method for determining the number
 	 * of CPUs, but it uses malloc internally, which causes untennable
 	 * recursion during malloc initialization.
 	 */
 	fd = open("/proc/cpuinfo", O_RDONLY);
 	if (fd == -1)
@@ -5115,30 +5116,33 @@ malloc_ncpus(void)
 	 * lines.  This treats hyperthreaded CPUs as multiple processors.
 	 */
 	column = 0;
 	ret = 0;
 	while (true) {
 		nread = read(fd, &buf, sizeof(buf));
 		if (nread <= 0)
 			break; /* EOF or error. */
-
-		if (buf[0] == '\n')
-			column = 0;
-		else if (column != -1) {
-			if (buf[0] == matchstr[column]) {
-				column++;
-				if (column == sizeof(matchstr) - 1) {
+		for (i = 0;i < nread;i++) {
+			char c = buf[i];
+			if (c == '\n')
+				column = 0;
+			else if (column != -1) {
+				if (c == matchstr[column]) {
+					column++;
+					if (column == sizeof(matchstr) - 1) {
+						column = -1;
+						ret++;
+					}
+				} else
 					column = -1;
-					ret++;
-				}
-			} else
-				column = -1;
+			}
 		}
 	}
+
 	if (ret == 0)
 		ret = 1; /* Something went wrong in the parser. */
 	close(fd);
 
 	return (ret);
 }
 #elif (defined(MOZ_MEMORY_DARWIN))
 #include <mach/mach_init.h>