diff --git a/init/init.cpp b/init/init.cpp
index 60fcf64..2500985 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -380,7 +380,8 @@
 
     if ((svc->flags & SVC_EXEC) != 0) {
         INFO("SVC_EXEC pid %d (uid %d gid %d+%zu context %s) started; waiting...\n",
-             svc->pid, svc->uid, svc->gid, svc->nr_supp_gids, svc->seclabel);
+             svc->pid, svc->uid, svc->gid, svc->nr_supp_gids,
+             svc->seclabel ? : "default");
         waiting_for_exec = true;
     }
 
diff --git a/init/init_parser.cpp b/init/init_parser.cpp
index df049ed..f975b6c 100644
--- a/init/init_parser.cpp
+++ b/init/init_parser.cpp
@@ -664,6 +664,7 @@
 
 service* make_exec_oneshot_service(int nargs, char** args) {
     // Parse the arguments: exec [SECLABEL [UID [GID]*] --] COMMAND ARGS...
+    // SECLABEL can be a - to denote default
     int command_arg = 1;
     for (int i = 1; i < nargs; ++i) {
         if (strcmp(args[i], "--") == 0) {
@@ -689,7 +690,7 @@
         return NULL;
     }
 
-    if (command_arg > 2) {
+    if ((command_arg > 2) && strcmp(args[1], "-")) {
         svc->seclabel = args[1];
     }
     if (command_arg > 3) {
diff --git a/init/readme.txt b/init/readme.txt
index 6b9c42d..c213041 100644
--- a/init/readme.txt
+++ b/init/readme.txt
@@ -180,7 +180,7 @@
    Fork and execute command with the given arguments. The command starts
    after "--" so that an optional security context, user, and supplementary
    groups can be provided. No other commands will be run until this one
-   finishes.
+   finishes. <seclabel> can be a - to denote default.
 
 export <name> <value>
    Set the environment variable <name> equal to <value> in the
diff --git a/liblog/log_time.cpp b/liblog/log_time.cpp
index 50742df..9d5ea0e 100644
--- a/liblog/log_time.cpp
+++ b/liblog/log_time.cpp
@@ -22,7 +22,7 @@
 
 #include <log/log_read.h>
 
-const char log_time::default_format[] = "%m-%d %H:%M:%S.%3q";
+const char log_time::default_format[] = "%m-%d %H:%M:%S.%q";
 const timespec log_time::EPOCH = { 0, 0 };
 
 // Add %#q for fractional seconds to standard strptime function
diff --git a/logcat/Android.mk b/logcat/Android.mk
index f46a4de..7115f9b 100644
--- a/logcat/Android.mk
+++ b/logcat/Android.mk
@@ -5,7 +5,7 @@
 
 LOCAL_SRC_FILES:= logcat.cpp event.logtags
 
-LOCAL_SHARED_LIBRARIES := liblog
+LOCAL_SHARED_LIBRARIES := liblog libbase libcutils
 
 LOCAL_MODULE := logcat
 
diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index 2c2d785..6d7740e 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -1,29 +1,38 @@
 // Copyright 2006-2015 The Android Open Source Project
 
+#include <arpa/inet.h>
 #include <assert.h>
 #include <ctype.h>
+#include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <math.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdarg.h>
 #include <string.h>
-#include <signal.h>
-#include <time.h>
-#include <unistd.h>
 #include <sys/cdefs.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
-#include <arpa/inet.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
 
+#include <memory>
+#include <string>
+
+#include <base/file.h>
+#include <base/strings.h>
+#include <cutils/sched_policy.h>
 #include <cutils/sockets.h>
+#include <log/event_tag_map.h>
 #include <log/log.h>
 #include <log/log_read.h>
-#include <log/logger.h>
 #include <log/logd.h>
+#include <log/logger.h>
 #include <log/logprint.h>
-#include <log/event_tag_map.h>
 
 #define DEFAULT_MAX_ROTATED_LOGS 4
 
@@ -202,7 +211,15 @@
         g_outFD = STDOUT_FILENO;
 
     } else {
-        struct stat statbuf;
+        if (set_sched_policy(0, SP_BACKGROUND) < 0) {
+            fprintf(stderr, "failed to set background scheduling policy\n");
+        }
+
+        struct sched_param param;
+        memset(&param, 0, sizeof(param));
+        if (sched_setscheduler((pid_t) 0, SCHED_BATCH, &param) < 0) {
+            fprintf(stderr, "failed to set to batch scheduler\n");
+        }
 
         g_outFD = openLogFile (g_outputFileName);
 
@@ -210,6 +227,7 @@
             logcat_panic(false, "couldn't open output file");
         }
 
+        struct stat statbuf;
         if (fstat(g_outFD, &statbuf) == -1) {
             close(g_outFD);
             logcat_panic(false, "couldn't get output file stat\n");
@@ -231,7 +249,7 @@
     fprintf(stderr, "options include:\n"
                     "  -s              Set default filter to silent.\n"
                     "                  Like specifying filterspec '*:S'\n"
-                    "  -f <filename>   Log to file. Default to stdout\n"
+                    "  -f <filename>   Log to file. Default is stdout\n"
                     "  -r <kbytes>     Rotate log every kbytes. Requires -f\n"
                     "  -n <count>      Sets max number of rotated logs to <count>, default 4\n"
                     "  -v <format>     Sets the log print format, where <format> is:\n\n"
@@ -352,6 +370,86 @@
     exit(EXIT_FAILURE);
 }
 
+static const char g_defaultTimeFormat[] = "%m-%d %H:%M:%S.%q";
+
+// Find last logged line in gestalt of all matching existing output files
+static log_time lastLogTime(char *outputFileName) {
+    log_time retval(log_time::EPOCH);
+    if (!outputFileName) {
+        return retval;
+    }
+
+    log_time now(CLOCK_REALTIME);
+
+    std::string directory;
+    char *file = strrchr(outputFileName, '/');
+    if (!file) {
+        directory = ".";
+        file = outputFileName;
+    } else {
+        *file = '\0';
+        directory = outputFileName;
+        *file = '/';
+        ++file;
+    }
+    size_t len = strlen(file);
+    log_time modulo(0, NS_PER_SEC);
+    std::unique_ptr<DIR, int(*)(DIR*)>dir(opendir(directory.c_str()), closedir);
+    struct dirent *dp;
+    while ((dp = readdir(dir.get())) != NULL) {
+        if ((dp->d_type != DT_REG)
+                || strncmp(dp->d_name, file, len)
+                || (dp->d_name[len]
+                    && ((dp->d_name[len] != '.')
+                        || !isdigit(dp->d_name[len+1])))) {
+            continue;
+        }
+
+        std::string file_name = directory;
+        file_name += "/";
+        file_name += dp->d_name;
+        std::string file;
+        if (!android::base::ReadFileToString(file_name, &file)) {
+            continue;
+        }
+
+        bool found = false;
+        for (const auto& line : android::base::Split(file, "\n")) {
+            log_time t(log_time::EPOCH);
+            char *ep = t.strptime(line.c_str(), g_defaultTimeFormat);
+            if (!ep || (*ep != ' ')) {
+                continue;
+            }
+            // determine the time precision of the logs (eg: msec or usec)
+            for (unsigned long mod = 1UL; mod < modulo.tv_nsec; mod *= 10) {
+                if (t.tv_nsec % (mod * 10)) {
+                    modulo.tv_nsec = mod;
+                    break;
+                }
+            }
+            // We filter any times later than current as we may not have the
+            // year stored with each log entry. Also, since it is possible for
+            // entries to be recorded out of order (very rare) we select the
+            // maximum we find just in case.
+            if ((t < now) && (t > retval)) {
+                retval = t;
+                found = true;
+            }
+        }
+        // We count on the basename file to be the definitive end, so stop here.
+        if (!dp->d_name[len] && found) {
+            break;
+        }
+    }
+    if (retval == log_time::EPOCH) {
+        return retval;
+    }
+    // tail_time prints matching or higher, round up by the modulo to prevent
+    // a replay of the last entry we have just checked.
+    retval += modulo;
+    return retval;
+}
+
 } /* namespace android */
 
 
@@ -417,12 +515,11 @@
                 /* FALLTHRU */
             case 'T':
                 if (strspn(optarg, "0123456789") != strlen(optarg)) {
-                    char *cp = tail_time.strptime(optarg,
-                                                  log_time::default_format);
+                    char *cp = tail_time.strptime(optarg, g_defaultTimeFormat);
                     if (!cp) {
                         logcat_panic(false,
                                     "-%c \"%s\" not in \"%s\" time format\n",
-                                    ret, optarg, log_time::default_format);
+                                    ret, optarg, g_defaultTimeFormat);
                     }
                     if (*cp) {
                         char c = *cp;
@@ -545,9 +642,11 @@
             break;
 
             case 'f':
+                if ((tail_time == log_time::EPOCH) && (tail_lines != 0)) {
+                    tail_time = lastLogTime(optarg);
+                }
                 // redirect output to a file
                 g_outputFileName = optarg;
-
             break;
 
             case 'r':
diff --git a/logd/Android.mk b/logd/Android.mk
index 73da8dc..615d030 100644
--- a/logd/Android.mk
+++ b/logd/Android.mk
@@ -41,4 +41,15 @@
 
 include $(BUILD_EXECUTABLE)
 
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := logpersist.start
+LOCAL_MODULE_TAGS := debug
+LOCAL_MODULE_CLASS := EXECUTABLES
+LOCAL_MODULE_PATH := $(bin_dir)
+LOCAL_SRC_FILES := logpersist
+ALL_TOOLS := logpersist.start logpersist.stop logpersist.cat
+LOCAL_POST_INSTALL_CMD := $(hide) $(foreach t,$(filter-out $(LOCAL_MODULE),$(ALL_TOOLS)),ln -sf $(LOCAL_MODULE) $(TARGET_OUT)/bin/$(t);)
+include $(BUILD_PREBUILT)
+
 include $(call first-makefiles-under,$(LOCAL_PATH))
diff --git a/logd/README.property b/logd/README.property
index ad7d0cd..a472efd 100644
--- a/logd/README.property
+++ b/logd/README.property
@@ -10,6 +10,8 @@
                                          default false
 ro.build.type               string       if user, logd.statistics & logd.klogd
                                          default false
+persist.logd.logpersistd    string       Enable logpersist daemon, "logcatd"
+                                         turns on logcat -f in logd context
 persist.logd.size          number 256K   default size of the buffer for all
                                          log ids at initial startup, at runtime
                                          use: logcat -b all -G <value>
diff --git a/logd/logpersist b/logd/logpersist
new file mode 100755
index 0000000..215e1e2
--- /dev/null
+++ b/logd/logpersist
@@ -0,0 +1,36 @@
+#! /system/bin/sh
+# logpersist cat start and stop handlers
+data=/data/misc/logd
+property=persist.logd.logpersistd
+service=logcatd
+progname="${0##*/}"
+if [ X"${1}" = "-h" -o X"${1}" = X"--help" ]; then
+  echo "${progname%.*}.cat            - dump current ${service%d} logs"
+  echo "${progname%.*}.start          - start ${service} service"
+  echo "${progname%.*}.stop [--clear] - stop ${service} service"
+  exit 0
+fi
+case ${progname} in
+*.cat)
+  su 1036 ls "${data}" |
+  tr -d '\r' |
+  sort -ru |
+  sed "s#^#${data}/#" |
+  su 1036 xargs cat
+  ;;
+*.start)
+  su 0 setprop ${property} ${service}
+  getprop ${property}
+  sleep 1
+  ps -t | grep "${data##*/}.*${service%d}"
+  ;;
+*.stop)
+  su 0 stop ${service}
+  su 0 setprop ${property} ""
+  [ X"${1}" != X"-c" -a X"${1}" != X"--clear" ] ||
+  ( sleep 1 ; su 1036,9998 rm -rf "${data}" )
+  ;;
+*)
+  echo "Unexpected command ${0##*/} ${@}" >&2
+  exit 1
+esac
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 0966038..1f421c5 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -649,3 +649,17 @@
     class late_start
     user root
     oneshot
+
+on property:persist.logd.logpersistd=logcatd
+    # all exec/services are called with umask(077), so no gain beyond 0700
+    mkdir /data/misc/logd 0700 logd log
+    # logd for write to /data/misc/logd, log group for read from pstore (-L)
+    exec - logd log -- /system/bin/logcat -L -b all -v threadtime -v usec -v printable -D -f /data/misc/logd/logcat -r 64 -n 256
+    start logcatd
+
+service logcatd /system/bin/logcat -b all -v threadtime -v usec -v printable -D -f /data/misc/logd/logcat -r 64 -n 256
+    class late_start
+    disabled
+    # logd for write to /data/misc/logd, log group for read from log daemon
+    user logd
+    group log
diff --git a/rootdir/init.trace.rc b/rootdir/init.trace.rc
index cd8d350..50944e6 100644
--- a/rootdir/init.trace.rc
+++ b/rootdir/init.trace.rc
@@ -1,6 +1,6 @@
 ## Permissions to allow system-wide tracing to the kernel trace buffer.
 ##
-on early-boot
+on boot
 
 # Allow writing to the kernel trace log.
     chmod 0222 /sys/kernel/debug/tracing/trace_marker