diff --git a/Makefile b/Makefile
index 1329ee8..2cdb525 100644
--- a/Makefile
+++ b/Makefile
@@ -593,7 +593,7 @@ build/filesystem.bin: \
 		filesystem/bin/tar
 	-$(FUMOUNT) build/filesystem/
 	rm -rf $@ build/filesystem/
-	dd if=/dev/zero of=$@ bs=1M count=128
+	dd if=/dev/zero of=$@ bs=1M count=64
 	cargo run --manifest-path schemes/redoxfs/Cargo.toml --release --bin redoxfs-mkfs $@
 	mkdir -p build/filesystem/
 	cargo build --manifest-path schemes/redoxfs/Cargo.toml --release --bin redoxfs
diff --git a/arch/x86_64/src/lib.rs b/arch/x86_64/src/lib.rs
index dc30d69..3a98ba0 100644
--- a/arch/x86_64/src/lib.rs
+++ b/arch/x86_64/src/lib.rs
@@ -37,7 +37,7 @@ pub extern crate x86;
     /// Offset to kernel heap
     pub const KERNEL_HEAP_OFFSET: usize = KERNEL_OFFSET + PML4_SIZE/2;
     /// Size of kernel heap
-    pub const KERNEL_HEAP_SIZE: usize = 256 * 1024 * 1024; // 256 MB
+    pub const KERNEL_HEAP_SIZE: usize = 128 * 1024 * 1024; // 128 MB
 
     /// Offset to kernel percpu variables
     //TODO: Use 64-bit fs offset to enable this pub const KERNEL_PERCPU_OFFSET: usize = KERNEL_HEAP_OFFSET - PML4_SIZE;