diff --git a/Cargo.lock b/Cargo.lock
index cbd4461c9c..c8d29e3b7a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -380,6 +380,11 @@ name = "fnv"
 version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "fs_extra"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "fsevent"
 version = "0.2.17"
@@ -551,6 +556,34 @@ name = "itoa"
 version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "jemalloc-ctl"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "jemalloc-sys 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.48 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "jemalloc-sys"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fs_extra 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.48 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "jemallocator"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "jemalloc-sys 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.48 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "join_to_string"
 version = "0.1.3"
@@ -920,6 +953,8 @@ dependencies = [
  "fst 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "insta 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "jemalloc-ctl 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "jemallocator 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "join_to_string 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1866,6 +1901,7 @@ dependencies = [
 "checksum filetime 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "a2df5c1a8c4be27e7707789dc42ae65976e60b394afd293d1419ab915833e646"
 "checksum flexi_logger 0.10.5 (registry+https://github.com/rust-lang/crates.io-index)" = "bbd731387787f54fa333fa426e173fe42ea3d1123636b2b27ad802025fc5d182"
 "checksum fnv 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "2fad85553e09a6f881f739c29f0b00b0f01357c743266d478b68951ce23285f3"
+"checksum fs_extra 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5f2a4a2034423744d2cc7ca2068453168dcdb82c438419e639a26bd87839c674"
 "checksum fsevent 0.2.17 (registry+https://github.com/rust-lang/crates.io-index)" = "c4bbbf71584aeed076100b5665ac14e3d85eeb31fdbb45fbd41ef9a682b5ec05"
 "checksum fsevent-sys 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "1a772d36c338d07a032d5375a36f15f9a7043bf0cb8ce7cee658e037c6032874"
 "checksum fst 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "db72126ca7dff566cdbbdd54af44668c544897d9d3862b198141f176f1238bdf"
@@ -1885,6 +1921,9 @@ dependencies = [
 "checksum iovec 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "dbe6e417e7d0975db6512b90796e8ce223145ac4e33c377e4a42882a0e88bb08"
 "checksum itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5b8467d9c1cebe26feb08c640139247fac215782d35371ade9a2136ed6085358"
 "checksum itoa 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1306f3464951f30e30d12373d31c79fbd52d236e5e896fd92f96ec7babbbe60b"
+"checksum jemalloc-ctl 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4e93b0f37e7d735c6b610176d5b1bde8e1621ff3f6f7ac23cdfa4e7f7d0111b5"
+"checksum jemalloc-sys 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "bfc62c8e50e381768ce8ee0428ee53741929f7ebd73e4d83f669bcf7693e00ae"
+"checksum jemallocator 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "9f0cd42ac65f758063fea55126b0148b1ce0a6354ff78e07a4d6806bc65c4ab3"
 "checksum join_to_string 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "4dc7a5290e8c2606ce2be49f456d50f69173cb96d1541e4f66e34ac8b331a98f"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
diff --git a/crates/ra_ide_api/Cargo.toml b/crates/ra_ide_api/Cargo.toml
index 79e473463f..ad9dd20882 100644
--- a/crates/ra_ide_api/Cargo.toml
+++ b/crates/ra_ide_api/Cargo.toml
@@ -14,6 +14,8 @@ fst = "0.3.1"
 rustc-hash = "1.0"
 parking_lot = "0.7.0"
 unicase = "2.2.0"
+jemallocator = "0.1.9"
+jemalloc-ctl = "0.2.0"
 
 ra_syntax = { path = "../ra_syntax" }
 ra_ide_api_light = { path = "../ra_ide_api_light" }
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index a7caac02d0..dc531e068d 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -59,6 +59,11 @@ pub use ra_db::{
     Canceled, CrateGraph, CrateId, FileId, FilePosition, FileRange, SourceRootId
 };
 
+// We use jemalloc mainly to get heap usage statistics, actual performance
+// differnece is not measures.
+#[global_allocator]
+static ALLOC: jemallocator::Jemalloc = jemallocator::Jemalloc;
+
 pub type Cancelable<T> = Result<T, Canceled>;
 
 #[derive(Default)]
diff --git a/crates/ra_ide_api/src/status.rs b/crates/ra_ide_api/src/status.rs
index 0dde30ae01..686ab97d28 100644
--- a/crates/ra_ide_api/src/status.rs
+++ b/crates/ra_ide_api/src/status.rs
@@ -30,11 +30,12 @@ pub(crate) fn status(db: &RootDatabase) -> String {
         interner.len()
     };
     format!(
-        "{}\n{}\n{}\nn_defs {}\nGC {:?} seconds ago",
+        "{}\n{}\n{}\nn_defs {}\n\njemalloc: {}\nGC {:?} seconds ago",
         files_stats,
         symbols_stats,
         syntax_tree_stats,
         n_defs,
+        MemoryStats::current(),
         db.last_gc.elapsed().as_secs(),
     )
 }
@@ -126,6 +127,31 @@ impl FromIterator<TableEntry<SourceRootId, Arc<SymbolIndex>>> for LibrarySymbols
     }
 }
 
+struct MemoryStats {
+    allocated: Bytes,
+    resident: Bytes,
+}
+
+impl MemoryStats {
+    fn current() -> MemoryStats {
+        jemalloc_ctl::epoch().unwrap();
+        MemoryStats {
+            allocated: Bytes(jemalloc_ctl::stats::allocated().unwrap()),
+            resident: Bytes(jemalloc_ctl::stats::resident().unwrap()),
+        }
+    }
+}
+
+impl fmt::Display for MemoryStats {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            fmt,
+            "{} allocated {} resident",
+            self.allocated, self.resident,
+        )
+    }
+}
+
 #[derive(Default)]
 struct Bytes(usize);