diff --git a/README.md b/README.md
index 15170db9c..dd9d19215 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,7 @@ wget https://justine.lol/cosmopolitan/cosmopolitan.zip
 unzip cosmopolitan.zip
 printf 'main() { printf("hello world\\n"); }\n' >hello.c
 gcc -g -Os -static -nostdlib -nostdinc -fno-pie -no-pie -mno-red-zone \
-  -fno-omit-frame-pointer -pg -mnop-mcount \
+  -fno-omit-frame-pointer -pg -mnop-mcount -mno-tls-direct-seg-refs \
   -o hello.com.dbg hello.c -fuse-ld=bfd -Wl,-T,ape.lds \
   -include cosmopolitan.h crt.o ape-no-modify-self.o cosmopolitan.a
 objcopy -S -O binary hello.com.dbg hello.com
diff --git a/examples/life.c b/examples/life.c
index 5e8dfe9c4..b61489df7 100644
--- a/examples/life.c
+++ b/examples/life.c
@@ -8,4 +8,6 @@
 ╚─────────────────────────────────────────────────────────────────*/
 #endif
 
-int main() { return 42; }
+int main() {
+  return 42;
+}
diff --git a/libc/calls/netbsdtramp.S b/libc/calls/netbsdtramp.S
index e0493b16e..3f4699933 100644
--- a/libc/calls/netbsdtramp.S
+++ b/libc/calls/netbsdtramp.S
@@ -21,9 +21,9 @@
 
 __restore_rt_netbsd:
 	mov	%r15,%rdi
-	mov	$308,%rax			# setcontext
+	mov	$308,%eax			# setcontext
 	syscall
-	mov	$-1,%edi
+	or	$-1,%edi
 	mov	$1,%rax				# exit
 	syscall
 	.endfn	__restore_rt_netbsd,globl,hidden
diff --git a/libc/calls/sigaction.c b/libc/calls/sigaction.c
index 16d285750..4f8afaabc 100644
--- a/libc/calls/sigaction.c
+++ b/libc/calls/sigaction.c
@@ -205,6 +205,11 @@ static int __sigaction(int sig, const struct sigaction *act,
       arg4 = (int64_t)(intptr_t)oldact; /* from go code */
       arg5 = 0;
     } else if (IsNetbsd()) {
+      /* int __sigaction_sigtramp(int signum,
+                                  const struct sigaction *nsa,
+                                  struct sigaction *osa,
+                                  const void *tramp,
+                                  int vers); */
       if (ap) {
         arg4 = (int64_t)(intptr_t)&__restore_rt_netbsd;
         arg5 = 2; /* netbsd/lib/libc/arch/x86_64/sys/__sigtramp2.S */
diff --git a/libc/calls/strace.internal.h b/libc/calls/strace.internal.h
index 16c29f56d..ee247e005 100644
--- a/libc/calls/strace.internal.h
+++ b/libc/calls/strace.internal.h
@@ -7,7 +7,7 @@
 #include "libc/calls/struct/stat.h"
 #include "libc/runtime/runtime.h"
 
-#define _KERNTRACE 0 /* not configurable w/ flag yet */
+#define _KERNTRACE 1 /* not configurable w/ flag yet */
 #define _POLLTRACE 0 /* not configurable w/ flag yet */
 #define _DATATRACE 1 /* not configurable w/ flag yet */
 #define _NTTRACE   0 /* not configurable w/ flag yet */
diff --git a/libc/calls/struct/ucontext-netbsd.internal.h b/libc/calls/struct/ucontext-netbsd.internal.h
index a0c60e247..8d297c174 100644
--- a/libc/calls/struct/ucontext-netbsd.internal.h
+++ b/libc/calls/struct/ucontext-netbsd.internal.h
@@ -13,7 +13,6 @@ COSMOPOLITAN_C_START_
 #define _UC_TLSBASE     0x00080000
 #define _UC_SETSTACK    0x00010000
 #define _UC_CLRSTACK    0x00020000
-#define _UC_CLRSTACK    0x00020000
 
 union sigval_netbsd {
   int32_t sival_int;
diff --git a/libc/intrin/gettid.greg.c b/libc/intrin/gettid.greg.c
index a6d99227e..f3b08f6e9 100644
--- a/libc/intrin/gettid.greg.c
+++ b/libc/intrin/gettid.greg.c
@@ -54,7 +54,9 @@ int gettid(void) {
   int tid;
   if (__tls_enabled) {
     tid = *(int *)(__get_tls() + 0x38);
-    if (tid > 0) return tid;
+    if (tid > 0) {
+      return tid;
+    }
   }
   return sys_gettid();
 }
diff --git a/libc/log/oncrash.c b/libc/log/oncrash.c
index df6827ae2..b4cdae1db 100644
--- a/libc/log/oncrash.c
+++ b/libc/log/oncrash.c
@@ -35,6 +35,7 @@
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/nexgen32e/stackframe.h"
+#include "libc/nexgen32e/threaded.h"
 #include "libc/runtime/internal.h"
 #include "libc/runtime/pc.internal.h"
 #include "libc/runtime/runtime.h"
@@ -283,6 +284,7 @@ relegated void __oncrash(int sig, struct siginfo *si, ucontext_t *ctx) {
   int gdbpid, err;
   static int sync;
   static bool notpossible;
+  __tls_enabled = false;
   STRACE("__oncrash rip %x", ctx->uc_mcontext.rip);
   --__ftrace;
   --__strace;
diff --git a/libc/mem/unveil.c b/libc/mem/unveil.c
index a2ffbb61b..b830a11e6 100644
--- a/libc/mem/unveil.c
+++ b/libc/mem/unveil.c
@@ -194,7 +194,6 @@ static int sys_unveil_linux(const char *path, const char *permissions) {
  */
 int unveil(const char *path, const char *permissions) {
   int rc;
-  __enable_tls();
   if (IsLinux()) {
     rc = sys_unveil_linux(path, permissions);
   } else {
diff --git a/libc/runtime/arch_prctl.c b/libc/runtime/arch_prctl.c
index 2c958c5fb..9c6b2be84 100644
--- a/libc/runtime/arch_prctl.c
+++ b/libc/runtime/arch_prctl.c
@@ -199,7 +199,7 @@ int arch_prctl(int code, int64_t addr) {
     case METAL:
       return arch_prctl_msr(code, addr);
     case FREEBSD:
-      /* claims support but it appears not */
+      // TODO(jart): this should use sysarch()
       return arch_prctl_freebsd(code, addr);
     case OPENBSD:
       return arch_prctl_openbsd(code, addr);
diff --git a/libc/runtime/clone.c b/libc/runtime/clone.c
index b8e23638e..1c9a5eec4 100644
--- a/libc/runtime/clone.c
+++ b/libc/runtime/clone.c
@@ -565,21 +565,9 @@ static int CloneLinux(int (*func)(void *arg, int tid), char *stk, size_t stksz,
  *       either terminated or has finished using its stack memory
  *
  *     - `CLONE_SETTLS` is needed if you intend to specify the `tls`
- *       argument, which provides a fast-path solution for changing the
- *       appropriate TLS segment register within the child thread. The
- *       child thread may then obtain a reference to the TIB address you
- *       supplied, by calling __get_tls(). Your C library holds certain
- *       expectations about the layout of your Thread Information Block
- *       (TIB), which are all documented by __initialize_tls(). That
- *       function can be used to initialize the first positive 64 bytes
- *       of your TLS allocation, which is the memory Cosmopolitan Libc
- *       wants for itself (and negative addresses are reserved by the
- *       GNU Linker). Using this flag will transition the C runtime to a
- *       `__tls_enabled` state automatically. If you use TLS for just
- *       one thread, then you must be specify TLS for ALL THREADS. It's
- *       a good idea to do that since TLS can offer considerable (i.e.
- *       multiple orders of a magnitude) performance improvement for
- *       TID-dependent C library services, e.g. recursive mutexes.
+ *       argument, which after thread creation may be accessed using
+ *       __get_tls(). Doing this means that `errno`, gettid(), etc.
+ *       correctly work. Caveat emptor if you choose not to do this.
  *
  * @param arg is passed as an argument to `func` in the child thread
  * @param tls may be used to set the thread local storage segment;
@@ -594,8 +582,9 @@ int clone(void *func, void *stk, size_t stksz, int flags, void *arg, int *ptid,
   int rc;
   struct CloneArgs *wt;
 
-  if (flags & CLONE_SETTLS) __enable_tls();
-  if (flags & CLONE_THREAD) __enable_threads();
+  if (flags & CLONE_THREAD) {
+    __enable_threads();
+  }
 
   if (!func) {
     rc = einval();
diff --git a/libc/runtime/cosmo.S b/libc/runtime/cosmo.S
index eba8547f3..954e2e263 100644
--- a/libc/runtime/cosmo.S
+++ b/libc/runtime/cosmo.S
@@ -76,22 +76,14 @@ cosmo:	push	%rbp
 	ret
 	.endfn	cosmo,weak
 
-#if !IsTiny()
-//	Enable TLS early if _Thread_local is used
-//	In MODE=tiny you may need to explicitly call __enable_tls()
-//	Otherwise this would bloat life.com from 16kb → 32kb D:
+//	Enables Thread Local Storage.
 	.init.start 304,_init_tls
-	mov	$_tls_content,%eax
-	test	%eax,%eax
-	jz	1f
 	push	%rdi
 	push	%rsi
 	call	__enable_tls
 	pop	%rsi
 	pop	%rdi
-	jz	1f
-1:	.init.end 304,_init_tls
-#endif
+	.init.end 304,_init_tls
 
 #if !IsTiny()
 //	Creates deterministically addressed stack we can use
diff --git a/libc/runtime/enable_tls.c b/libc/runtime/enable_tls.c
index cfb74cf06..7bd2d3f24 100644
--- a/libc/runtime/enable_tls.c
+++ b/libc/runtime/enable_tls.c
@@ -16,12 +16,16 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/assert.h"
 #include "libc/bits/bits.h"
+#include "libc/bits/weaken.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/strace.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/dce.h"
 #include "libc/errno.h"
+#include "libc/intrin/kprintf.h"
+#include "libc/log/libfatal.internal.h"
 #include "libc/macros.internal.h"
 #include "libc/nexgen32e/threaded.h"
 #include "libc/nt/thread.h"
@@ -52,12 +56,35 @@ __msabi extern typeof(TlsAlloc) *const __imp_TlsAlloc;
 
 extern unsigned char __tls_mov_nt_rax[];
 extern unsigned char __tls_add_nt_rax[];
+_Alignas(long) static char __static_tls[5008];
 
 /**
  * Enables thread local storage.
+ *
+ * This function is always called by the core runtime to guarantee TLS
+ * is always available to your program. You must build your code using
+ * -mno-tls-direct-seg-refs if you want to use _Thread_local.
+ *
+ * You can use __get_tls() to get the linear address of your tib. When
+ * accessing TLS via privileged code you must use __get_tls_privileged
+ * because we need code morphing to support The New Technology and XNU
+ *
+ * On XNU and The New Technology, this function imposes 1ms of latency
+ * during startup for larger binaries like Python.
+ *
+ * If you don't want TLS and you're sure you're not using it, then you
+ * can disable it as follows:
+ *
+ *     int main() {
+ *       __tls_enabled = false;
+ *       // do stuff
+ *     }
+ *
+ * This is useful if you want to wrestle back control of %fs using the
+ * arch_prctl() function. However, such programs might not be portable
+ * and your `errno` variable also won't be thread safe anymore.
  */
 privileged void __enable_tls(void) {
-  if (__tls_enabled) return;
   STRACE("__enable_tls()");
 
   // allocate tls memory for main process
@@ -74,20 +101,42 @@ privileged void __enable_tls(void) {
   size_t siz;
   cthread_t tib;
   char *mem, *tls;
-  siz = ROUNDUP(_TLSZ + _TIBZ, FRAMESIZE);
-  mem = _mapanon(siz);
+  siz = ROUNDUP(_TLSZ + _TIBZ, alignof(__static_tls));
+  if (siz <= sizeof(__static_tls)) {
+    // if tls requirement is small then use the static tls block
+    // which helps avoid a system call for appes with little tls
+    // this is crucial to keeping life.com 16 kilobytes in size!
+    _Static_assert(alignof(__static_tls) >= alignof(cthread_t));
+    mem = __static_tls;
+  } else {
+    // if this binary needs a hefty tls block then we'll bank on
+    // malloc() being linked, which links _mapanon().  otherwise
+    // if you exceed this, you need to STATIC_YOINK("_mapanon").
+    // please note that it's probably too early to call calloc()
+    assert(weaken(_mapanon));
+    siz = ROUNDUP(siz, FRAMESIZE);
+    mem = weaken(_mapanon)(siz);
+    assert(mem);
+  }
   tib = (cthread_t)(mem + siz - _TIBZ);
   tls = mem + siz - _TIBZ - _TLSZ;
   tib->self = tib;
   tib->self2 = tib;
   tib->err = __errno;
-  tib->tid = sys_gettid();
-  memmove(tls, _tdata_start, _TLDZ);
+  if (IsLinux()) {
+    // gnu/systemd guarantees pid==tid for the main thread so we can
+    // avoid issuing a superfluous system call at startup in program
+    tib->tid = __pid;
+  } else {
+    tib->tid = sys_gettid();
+  }
+  __repmovsb(tls, _tdata_start, _TLDZ);
 
   // ask the operating system to change the x86 segment register
   int ax, dx;
   if (IsWindows()) {
     __tls_index = __imp_TlsAlloc();
+    assert(0 <= __tls_index && __tls_index < 64);
     asm("mov\t%1,%%gs:%0" : "=m"(*((long *)0x1480 + __tls_index)) : "r"(tib));
   } else if (IsFreebsd()) {
     asm volatile("syscall"
@@ -95,9 +144,12 @@ privileged void __enable_tls(void) {
                  : "0"(__NR_sysarch), "D"(AMD64_SET_FSBASE), "S"(tib)
                  : "rcx", "r11", "memory", "cc");
   } else if (IsNetbsd()) {
+    // netbsd has sysarch(X86_SET_FSBASE) but we can't use that because
+    // signal handlers will cause it to be reset due to net setting the
+    // _mc_tlsbase field in struct mcontext_netbsd.
     asm volatile("syscall"
                  : "=a"(ax), "=d"(dx)
-                 : "0"(__NR_sysarch), "D"(X86_SET_FSBASE), "S"(tib)
+                 : "0"(__NR__lwp_setprivate), "D"(tib)
                  : "rcx", "r11", "memory", "cc");
   } else if (IsXnu()) {
     asm volatile("syscall"
@@ -179,7 +231,7 @@ privileged void __enable_tls(void) {
       }
 
       // we're checking for the following expression:
-      //   0144 == p[0] &&           // fs
+      //   0144 == p[0] &&           // %fs
       //   0110 == p[1] &&           // rex.w (64-bit operand size)
       //   (0213 == p[2] ||          // mov reg/mem → reg (word-sized)
       //   0003 == p[2]) &&          // add reg/mem → reg (word-sized)
@@ -195,7 +247,7 @@ privileged void __enable_tls(void) {
           !p[8]) {
 
         // now change the code
-        p[0] = 0145;  // this changes gs segment to fs segment
+        p[0] = 0145;                       // change %fs to %gs
         p[5] = (dis & 0x000000ff) >> 000;  // displacement
         p[6] = (dis & 0x0000ff00) >> 010;  // displacement
         p[7] = (dis & 0x00ff0000) >> 020;  // displacement
diff --git a/libc/runtime/ftracer.c b/libc/runtime/ftracer.c
index 2e63d542d..951bc9a51 100644
--- a/libc/runtime/ftracer.c
+++ b/libc/runtime/ftracer.c
@@ -92,7 +92,6 @@ privileged void ftracer(void) {
 
 textstartup int ftrace_install(void) {
   if (GetSymbolTable()) {
-    __enable_tls();
     g_stackdigs = LengthInt64Thousands(GetStackSize());
     return __hook(ftrace_hook, GetSymbolTable());
   } else {
diff --git a/libc/runtime/internal.h b/libc/runtime/internal.h
index c0e20fc5c..f61d4d8fb 100644
--- a/libc/runtime/internal.h
+++ b/libc/runtime/internal.h
@@ -27,7 +27,7 @@ extern unsigned char _tls_size[];
 extern unsigned char _tls_content[];
 
 void _init(void) hidden;
-void __enable_tls(void) hidden;
+void __enable_tls(void);
 void __enable_threads(void) hidden;
 void __restorewintty(void) hidden;
 void *__cxa_finalize(void *) hidden;
diff --git a/libc/runtime/mapanon.c b/libc/runtime/mapanon.c
index 1291a5ec8..12be768d2 100644
--- a/libc/runtime/mapanon.c
+++ b/libc/runtime/mapanon.c
@@ -55,15 +55,16 @@
  *
  * That is performed automatically for unit test executables.
  *
- * @return memory map address on success, or null w/ errrno
+ * @return memory map address on success, or null w/ errno
  */
 void *_mapanon(size_t size) {
-  /* asan runtime depends on this function */
   void *m;
   m = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
-  if (m == MAP_FAILED && weaken(__oom_hook)) {
-    weaken(__oom_hook)(size);
-    return 0;
+  if (m != MAP_FAILED) {
+    return m;
   }
-  return m;
+  if (errno == ENOMEM && weaken(__oom_hook)) {
+    weaken(__oom_hook)(size);
+  }
+  return 0;
 }
diff --git a/libc/runtime/morph.greg.c b/libc/runtime/morph.greg.c
index bda8dc526..59ad7ff2a 100644
--- a/libc/runtime/morph.greg.c
+++ b/libc/runtime/morph.greg.c
@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #define ShouldUseMsabiAttribute() 1
+#include "libc/assert.h"
 #include "libc/bits/asmflag.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/strace.internal.h"
@@ -58,10 +59,28 @@ static privileged void __morph_mprotect(void *addr, size_t size, int prot,
  * @return 0 on success, or -1 w/ errno
  */
 privileged void __morph_begin(void) {
+  int ax;
+  bool cf;
+  intptr_t dx;
   sigset_t ss = {{-1, -1}};
   STRACE("__morph_begin()");
   if (!IsWindows()) {
-    sys_sigprocmask(SIG_BLOCK, &ss, &oldss);
+    if (!IsOpenbsd()) {
+      asm volatile("mov\t$8,%%r10d\n\t"
+                   "syscall"
+                   : "=a"(ax), "=d"(dx)
+                   : "0"(__NR_sigprocmask), "D"(SIG_BLOCK), "S"(&ss),
+                     "1"(&oldss)
+                   : "rcx", "r10", "r11", "memory", "cc");
+      assert(!ax);
+    } else {
+      asm volatile(CFLAG_ASM("syscall")
+                   : CFLAG_CONSTRAINT(cf), "=a"(ax), "=d"(dx)
+                   : "1"(__NR_sigprocmask), "D"(SIG_BLOCK), "S"(-1u)
+                   : "rcx", "r11", "memory");
+      oldss.__bits[0] = ax & 0xffffffff;
+      assert(!cf);
+    }
   }
   __morph_mprotect(_base, __privileged_addr - _base, PROT_READ | PROT_WRITE,
                    kNtPageWritecopy);
@@ -71,10 +90,28 @@ privileged void __morph_begin(void) {
  * Begins code morphing execuatble.
  */
 privileged void __morph_end(void) {
+  int ax;
+  long dx;
+  bool cf;
   __morph_mprotect(_base, __privileged_addr - _base, PROT_READ | PROT_EXEC,
                    kNtPageExecuteRead);
   if (!IsWindows()) {
-    sys_sigprocmask(SIG_SETMASK, &oldss, 0);
+    if (!IsOpenbsd()) {
+      asm volatile("mov\t$8,%%r10d\n\t"
+                   "syscall"
+                   : "=a"(ax), "=d"(dx)
+                   : "0"(__NR_sigprocmask), "D"(SIG_SETMASK), "S"(&oldss),
+                     "1"(0)
+                   : "rcx", "r10", "r11", "memory", "cc");
+      assert(!ax);
+    } else {
+      asm volatile(CFLAG_ASM("syscall")
+                   : CFLAG_CONSTRAINT(cf), "=a"(ax), "=d"(dx)
+                   : "1"(__NR_sigprocmask), "D"(SIG_SETMASK),
+                     "S"(oldss.__bits[0])
+                   : "rcx", "r11", "memory");
+      assert(!cf);
+    }
   }
   STRACE("__morph_end()");
 }
diff --git a/libc/sysv/syscalls.sh b/libc/sysv/syscalls.sh
index a5e12a0ff..5a65c2fea 100755
--- a/libc/sysv/syscalls.sh
+++ b/libc/sysv/syscalls.sh
@@ -48,7 +48,7 @@ scall	__sys_mmap		0x0c50c51dd20c5009	globl hidden # netbsd+openbsd:pad
 scall	sys_msync		0x115100041204101a	globl hidden
 scall	sys_mprotect		0x04a04a04a204a00a	globl hidden
 scall	__sys_munmap		0x049049049204900b	globl hidden
-scall	sys_sigaction		0x15402e1a0202e00d	globl hidden # rt_sigaction on Lunix; it's complicated on NetBSD
+scall	sys_sigaction		0x15402e1a0202e00d	globl hidden # rt_sigaction on Lunix; __sigaction_sigtramp() on NetBSD
 scall	__sys_sigprocmask	0x125030154214900e	globl hidden # a.k.a. rt_sigprocmask, openbsd:byvalue, a.k.a. pthread_sigmask
 scall	sys_ioctl		0x0360360362036010	globl hidden
 scall	sys_pread		0x0ad0ad1db2099011	globl hidden # a.k.a. pread64; netbsd+openbsd:pad
diff --git a/libc/thread/ctor.S b/libc/thread/ctor.S
deleted file mode 100644
index 8139b3d87..000000000
--- a/libc/thread/ctor.S
+++ /dev/null
@@ -1,27 +0,0 @@
-/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8     -*-│
-│vi: set et ft=asm ts=8 tw=8 fenc=utf-8                                     :vi│
-╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
-│                                                                              │
-│ Permission to use, copy, modify, and/or distribute this software for         │
-│ any purpose with or without fee is hereby granted, provided that the         │
-│ above copyright notice and this permission notice appear in all copies.      │
-│                                                                              │
-│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
-│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
-│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
-│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
-│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
-│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
-│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
-│ PERFORMANCE OF THIS SOFTWARE.                                                │
-╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/macros.internal.h"
-
-	.init.start 400,_main_thread_ctor
-	push	%rdi
-	push	%rsi
-	call	__enable_tls
-	pop	%rsi
-	pop	%rdi
-	.init.end 400,_main_thread_ctor
diff --git a/libc/thread/self.c b/libc/thread/self.c
index a4af248b9..a790a1ad7 100644
--- a/libc/thread/self.c
+++ b/libc/thread/self.c
@@ -20,8 +20,6 @@
 #include "libc/nexgen32e/threaded.h"
 #include "libc/thread/thread.h"
 
-STATIC_YOINK("_main_thread_ctor");
-
 /**
  * Returns thread descriptor of the current thread.
  */
diff --git a/libc/thread/sem.c b/libc/thread/sem.c
index 4187584ba..06b355984 100644
--- a/libc/thread/sem.c
+++ b/libc/thread/sem.c
@@ -20,8 +20,6 @@
 #include "libc/calls/calls.h"
 #include "libc/thread/thread.h"
 
-STATIC_YOINK("_main_thread_ctor");
-
 #define CTHREAD_THREAD_VAL_BITS 32
 
 static void Pause(int attempt) {
diff --git a/libc/thread/spawn.c b/libc/thread/spawn.c
index a144635a5..98788cc25 100644
--- a/libc/thread/spawn.c
+++ b/libc/thread/spawn.c
@@ -32,8 +32,6 @@
 #include "libc/thread/spawn.h"
 #include "libc/thread/thread.h"
 
-STATIC_YOINK("_main_thread_ctor");
-
 /**
  * @fileoverview Simple threading API
  *
diff --git a/test/libc/mem/malloc_test.c b/test/libc/mem/malloc_test.c
index 715617ae3..f336d1378 100644
--- a/test/libc/mem/malloc_test.c
+++ b/test/libc/mem/malloc_test.c
@@ -114,6 +114,12 @@ TEST(malloc, test) {
   for (i = 0; i < ARRAYLEN(fds); ++i) close(fds[i]);
 }
 
+TEST(memalign, roundsUpAlignmentToTwoPower) {
+  char *volatile p = memalign(129, 1);
+  ASSERT_EQ(0, (intptr_t)p & 255);
+  free(p);
+}
+
 void *bulk[1024];
 
 void BulkFreeBenchSetup(void) {
diff --git a/test/libc/runtime/arch_prctl_test.c b/test/libc/runtime/arch_prctl_test.c
index 01dc43760..14770aa47 100644
--- a/test/libc/runtime/arch_prctl_test.c
+++ b/test/libc/runtime/arch_prctl_test.c
@@ -19,9 +19,11 @@
 #include "libc/bits/segmentation.h"
 #include "libc/calls/calls.h"
 #include "libc/dce.h"
+#include "libc/nexgen32e/threaded.h"
 #include "libc/testlib/testlib.h"
 
 __attribute__((__constructor__)) static void init(void) {
+  __tls_enabled = false;
   pledge("stdio rpath", 0);
   errno = 0;
 }
diff --git a/test/libc/runtime/munmap_test.c b/test/libc/runtime/munmap_test.c
index a1309431b..01e541e2a 100644
--- a/test/libc/runtime/munmap_test.c
+++ b/test/libc/runtime/munmap_test.c
@@ -24,6 +24,7 @@
 #include "libc/intrin/kprintf.h"
 #include "libc/runtime/memtrack.internal.h"
 #include "libc/runtime/runtime.h"
+#include "libc/str/str.h"
 #include "libc/sysv/consts/map.h"
 #include "libc/sysv/consts/o.h"
 #include "libc/sysv/consts/prot.h"
@@ -66,6 +67,12 @@ TEST(munmap, doesntExist_doesntCare) {
   }
 }
 
+TEST(munmap, invalidParams) {
+  EXPECT_SYS(EINVAL, -1, munmap(0, 0));
+  EXPECT_SYS(EINVAL, -1, munmap((void *)0x100080000000, 0));
+  EXPECT_SYS(EINVAL, -1, munmap((void *)0x100080000001, FRAMESIZE));
+}
+
 TEST(munmap, test) {
   char *p;
   ASSERT_NE(MAP_FAILED, (p = mmap(0, FRAMESIZE, PROT_READ | PROT_WRITE,
@@ -75,12 +82,6 @@ TEST(munmap, test) {
   EXPECT_FALSE(MemoryExists(p));
 }
 
-TEST(munmap, invalidParams) {
-  EXPECT_SYS(EINVAL, -1, munmap(0, 0));
-  EXPECT_SYS(EINVAL, -1, munmap((void *)0x100080000000, 0));
-  EXPECT_SYS(EINVAL, -1, munmap((void *)0x100080000001, FRAMESIZE));
-}
-
 TEST(munmap, punchHoleInMemory) {
   char *p;
   ASSERT_NE(MAP_FAILED, (p = mmap(0, FRAMESIZE * 3, PROT_READ | PROT_WRITE,
diff --git a/test/libc/stdio/fputc_test.c b/test/libc/stdio/fputc_test.c
index 092e3139f..6062a362c 100644
--- a/test/libc/stdio/fputc_test.c
+++ b/test/libc/stdio/fputc_test.c
@@ -64,7 +64,6 @@ TEST(fgetc, testUnbuffered) {
 }
 
 BENCH(fputc, bench) {
-  __enable_tls();
   __enable_threads();
   FILE *f;
   ASSERT_NE(NULL, (f = fopen("/dev/null", "w")));
diff --git a/test/libc/thread/pthread_key_create_test.c b/test/libc/thread/pthread_key_create_test.c
index 52ccbac30..15cdc4bd2 100644
--- a/test/libc/thread/pthread_key_create_test.c
+++ b/test/libc/thread/pthread_key_create_test.c
@@ -38,9 +38,3 @@ TEST(pthread_key_create, testRunsDtors_becauseNoLeakReport) {
   EXPECT_EQ(0, pthread_setspecific(key, x));
   EXPECT_EQ(x, pthread_getspecific(key));
 }
-
-__attribute__((__constructor__)) static void init(void) {
-  if (IsTiny()) {
-    __enable_tls();
-  }
-}
diff --git a/third_party/dlmalloc/README.cosmo b/third_party/dlmalloc/README.cosmo
index d364ed7b6..c3b83321b 100644
--- a/third_party/dlmalloc/README.cosmo
+++ b/third_party/dlmalloc/README.cosmo
@@ -9,5 +9,7 @@ LICENSE
 
 LOCAL CHANGES
 
-  - Introduce __oom_hook()
-  - Favor pause (rather than sched_yield) for spin locks
+  - Use faster two power roundup for memalign()
+  - Poison maps to integrate with Address Sanitizer
+  - Introduce __oom_hook() by using _mapanon() vs. mmap()
+  - Wrap locks with __threaded check to improve perf lots
diff --git a/third_party/dlmalloc/dlmalloc.c b/third_party/dlmalloc/dlmalloc.c
index 827dd4867..c2d9cd467 100644
--- a/third_party/dlmalloc/dlmalloc.c
+++ b/third_party/dlmalloc/dlmalloc.c
@@ -5,7 +5,9 @@
 #include "libc/dce.h"
 #include "libc/errno.h"
 #include "libc/intrin/kprintf.h"
+#include "libc/macros.internal.h"
 #include "libc/mem/mem.h"
+#include "libc/nexgen32e/bsr.h"
 #include "libc/nexgen32e/rdtsc.h"
 #include "libc/rand/rand.h"
 #include "libc/runtime/runtime.h"
@@ -917,11 +919,8 @@ static void* internal_memalign(mstate m, size_t alignment, size_t bytes) {
   void* mem = 0;
   if (alignment <  MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */
     alignment = MIN_CHUNK_SIZE;
-  if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */
-    size_t a = MALLOC_ALIGNMENT << 1;
-    while (a < alignment) a <<= 1;
-    alignment = a;
-  }
+  /* alignment is 32+ bytes rounded up to nearest two power */
+  alignment = 2ul << bsrl(MAX(MIN_CHUNK_SIZE, alignment) - 1);
   if (bytes >= MAX_REQUEST - alignment) {
     if (m != 0)  { /* Test isn't needed but avoids compiler warning */
       MALLOC_FAILURE_ACTION;
diff --git a/third_party/dlmalloc/locks.inc b/third_party/dlmalloc/locks.inc
index 4c38271c0..0bf125f21 100644
--- a/third_party/dlmalloc/locks.inc
+++ b/third_party/dlmalloc/locks.inc
@@ -1,4 +1,5 @@
 // clang-format off
+#include "libc/calls/calls.h"
 #include "libc/nexgen32e/threaded.h"
 
 /* --------------------------- Lock preliminaries ------------------------ */
@@ -94,7 +95,7 @@ FORCEINLINE void x86_clear_lock(int* sl) {
 /* Plain spin locks use single word (embedded in malloc_states) */
 static dontinline int spin_acquire_lock(int *sl) {
   while (*(volatile int *)sl != 0 || CAS_LOCK(sl)) {
-    __builtin_ia32_pause();
+    sched_yield();
   }
   return 0;
 }
@@ -154,7 +155,7 @@ FORCEINLINE int recursive_acquire_lock(MLOCK_T *lk) {
       ++lk->c;
       return 0;
     }
-    __builtin_ia32_pause();
+    sched_yield();
   }
 }
 
diff --git a/third_party/dlmalloc/platform.inc b/third_party/dlmalloc/platform.inc
index 8b0cd9e71..d5c57893c 100644
--- a/third_party/dlmalloc/platform.inc
+++ b/third_party/dlmalloc/platform.inc
@@ -179,6 +179,8 @@
 /*
   ========================================================================
   To make a fully customizable malloc.h header file, cut everything
+#include "libc/sysv/consts/map.h"
+#include "libc/runtime/runtime.h"
   above this line, put into file malloc.h, edit to suit, and #include it
   on the next line, as well as in programs that use this malloc.
   ========================================================================
@@ -385,7 +387,7 @@ unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
 
 
 /* MORECORE and MMAP must return MFAIL on failure */
-#define MFAIL                ((void*)(MAX_SIZE_T))
+#define MFAIL                NULL
 #define CMFAIL               ((char*)(MFAIL)) /* defined for convenience */
 
 #if HAVE_MMAP
@@ -398,7 +400,7 @@ unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
 #endif /* MAP_ANON */
 #ifdef MAP_ANONYMOUS
 #define MMAP_FLAGS           (MAP_PRIVATE|MAP_ANONYMOUS)
-#define MMAP_DEFAULT(s)       mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0)
+#define MMAP_DEFAULT(s)       _mapanon(s)
 #else /* MAP_ANONYMOUS */
 /*
    Nearly all versions of mmap support MAP_ANONYMOUS, so the following
@@ -408,8 +410,8 @@ unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
 static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
 #define MMAP_DEFAULT(s) ((dev_zero_fd < 0) ? \
            (dev_zero_fd = open("/dev/zero", O_RDWR), \
-            mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
-            mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
+            mmap_no(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
+            mmap_no(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
 #endif /* MAP_ANONYMOUS */
 
 #define DIRECT_MMAP_DEFAULT(s) MMAP_DEFAULT(s)
diff --git a/third_party/dlmalloc/vespene.c b/third_party/dlmalloc/vespene.c
index da84f24cc..c47850ad4 100644
--- a/third_party/dlmalloc/vespene.c
+++ b/third_party/dlmalloc/vespene.c
@@ -16,24 +16,21 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/bits/weaken.h"
-#include "libc/calls/calls.h"
+#include "libc/dce.h"
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/asancodes.h"
-#include "libc/intrin/kprintf.h"
 #include "libc/runtime/runtime.h"
-#include "libc/sysv/consts/map.h"
-#include "libc/sysv/consts/prot.h"
+#include "third_party/dlmalloc/vespene.internal.h"
 
 /**
  * Acquires more system memory for dlmalloc.
+ * @return memory map address on success, or null w/ errno
  */
 void *dlmalloc_requires_more_vespene_gas(size_t size) {
   char *p;
-  if ((p = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS,
-                -1, 0)) != MAP_FAILED) {
-    if (weaken(__asan_poison)) {
-      weaken(__asan_poison)(p, size, kAsanHeapFree);
+  if ((p = _mapanon(size))) {
+    if (IsAsan()) {
+      __asan_poison(p, size, kAsanHeapFree);
     }
   }
   return p;
diff --git a/tool/plinko/plinko.c b/tool/plinko/plinko.c
index 90158369e..21823eeed 100644
--- a/tool/plinko/plinko.c
+++ b/tool/plinko/plinko.c
@@ -18,12 +18,14 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/intrin/kprintf.h"
 #include "libc/log/log.h"
+#include "libc/nexgen32e/threaded.h"
 #include "libc/stdio/stdio.h"
 #include "tool/plinko/lib/plinko.h"
 
 STATIC_YOINK("__zipos_get");
 
 int main(int argc, char *argv[]) {
+  __tls_enabled = false;
   Plinko(argc, argv);
   return 0;
 }