update readme

1 files changed, 18 insertions, 7 deletions

diff --git a/README b/README
index 0717846..6e2ba19 100644
--- a/README
+++ b/README
@@ -2,20 +2,31 @@
 
 A buddy allocator with zero metadata overhead.
 
-Benefits are:
+Benefits over buddy allocators that store a free-or-not bit on the block:
 
-    1. Very good use of space compared to traditional buddy allocators,
-       especially if you are frequently requesting power-of-two allocations.
+    1. When you request an allocation of 2^k, it only allocates 2^k space, not
+       2^{k+1} to account for the extra free-or-not-bit.
 
-    2. Still constant-time allocation and liberation.
+Benefits over buddy allocators that store a bitset:
 
-    3. The library is small, simple, and convenient to use. It even supports
+    1. You save at least a few MB in metadata, or more if you're allocating
+       huge amounts of space.
+
+    2. Comparably simple implementation; only ~250 loc, and there is no need to
+       track a metadata region.
+
+Features of the allocator shared with other buddy allocators include:
+
+    1. All operations are constant time/linear only in the number of address
+       bits.
+
+    2. The library is small, simple, and convenient to use. It even supports
        unaligned base addresses.
 
-    4. Support for realloc and reserving subregions (e.g., device MMIO
+    3. Support for realloc and reserving subregions (e.g., device MMIO
        addresses).
 
-    5. Core functionality is reasonably well-tested with an exhaustive
+    4. Core functionality is reasonably well-tested with an exhaustive
        implementation model checker.
 
 Caveats are: