在README中

For ARM（电脑需要安装arm-linux-gnueabi-gcc）:

应该改为gcc-arm-linux-gnueabi

no \n before lepdendstring
limit their lines

no valid information.

Lepv will show such information accordingly.

browser--lepv--lepd, found 1 time

$ df -h
Filesystem Size Used Avail Use% Mounted on
udev 126G 0 126G 0% /dev
tmpfs 26G 52M 26G 1% /run
/dev/mapper/ubuntu--vg-root 573G 411G 134G 76% /
tmpfs 126G 220K 126G 1% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 126G 0 126G 0% /sys/fs/cgroup
/dev/sda1 472M 169M 279M 38% /boot
tmpfs 26G 92K 26G 1% /run/user/1000

But the cmd_buff returned from busybox df_main is:
(gdb) p cmd_buff
$3 = "Filesystem", ' ' <repeats 16 times>, "Size Used Available Use% Mounted on\nudev", ' ' <repeats 20 times>, "125.9G 0 125.9G 0% /dev\ntmpfs", ' ' <repeats 20 times>, "25.2G 51.5M 25.1G 0% /run\n/dev/mapper/ubuntu--vg-root\n", ' ' <repeats 24 times>, "572.6G 410.3G 133.2G 75% /\ntmpfs", ' ' <repeats 19 times>, "125.9G 220.0K 125.9G 0% /dev/shm\ntmpfs", ' ' <repeats 21 times>, "5.0M 0 5.0M 0% /run/lock\ntmpfs", ' ' <repeats 19 times>, "125.9G 0 125.9G 0% /sys/fs/cgroup\n/dev/sda1", ' ' <repeats 15 times>, "471.6M 168.8M 278.4M 38% /boot\ntmpfs", ' ' <repeats 20 times>, "25.2G 92.0K 25.2G 0% /run/user/1000\n/dev/mapper/ubuntu--vg-root\n", ' ' <repeats 24 times>, "572.6G 410.3G 133.2G 75% /var/lib/docker/aufs\n", '\000' <repeats 7476 times>

There is unexpected \n after /dev/mapper/ubuntu--vg-root\n which results lepv parse error.

linuxep/lepd/libs/libsysstat.a: error adding symbols: Archive has no index; run ranlib to add one
collect2: error: ld returned 1 exit status
Makefile:65: recipe for target 'all' failed
make: *** [all] Error 1

1, replace pipe with buffer
2, replace printf with sprintf
3,make run_builtin_cmd as a thread handler
4,a semaphore is needed to control the count of thread

perf record -e sched:sched_stat_sleep -e sched:sched_switch -e sched:sched_process_exit -a -g -o perf.data.raw sleep 1

perf inject -s -i perf.data.raw -o perf.data

perf script

unknow sort specifier

In order to start continuous integration, i commited the .travis.yml .
And the repository need to start in travis-ci.org .
I wrote a blog to introduce how to do it simply :).

actflags in mpstat is not well reset.
reset it to 0 each time when calling mpstat_main

probably something wrong with iotop because it uses netlink.

lepd测试
一 运行环境
1.1 操作系统ubuntu，内核：
sam@brix:/data/lep/lepd$ uname -a
Linux brix 4.13.0-16-generic #19-Ubuntu SMP Wed Oct 11 18:35:14 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
1.2 firefox

1.3 lepd和lepv都运行在同一台机器上
1.4 硬件设备为一台brix，Intel(R) Celeron(R) 2955U @ 1.40GHz
lepd和lepv都运行在同一台机器上，有一块有线网卡，地址为192.168.20.200,有一块无线网卡，网址为192.168.43.46（DHCP）
sam@brix:/data/lep/lepd$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 74:d4:35:69:c8:a8 brd ff:ff:ff:ff:ff:ff
inet 192.168.20.200/24 brd 192.168.20.255 scope global enp3s0
valid_lft forever preferred_lft forever
inet6 fe80::b1e2:6be1:2841:3df1/64 scope link
valid_lft forever preferred_lft forever
3: wlp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether 6c:71:d9:b4:a8:ab brd ff:ff:ff:ff:ff:ff
inet 192.168.43.46/24 brd 192.168.43.255 scope global dynamic wlp2s0
valid_lft 2664sec preferred_lft 2664sec
inet6 fe80::a0cb:9f1b:5a34:2b1e/64 scope link
valid_lft forever preferred_lft forever
4: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:11:cc:39:24 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 scope global docker0
valid_lft forever preferred_lft forever
inet6 fe80::42:11ff:fecc:3924/64 scope link
valid_lft forever preferred_lft forever
12: veth6d89cfe@if11: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default
link/ether d6:e7:f0:b2:6d:92 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet6 fe80::d4e7:f0ff:feb2:6d92/64 scope link
valid_lft forever preferred_lft forever

二 测试步骤
2.1 运行lepd
root@brix:/data/lep/lepd# ./lepd &
2.2 运行lepv
root@brix:/data/lep/lepv# ./runContainer.sh
2.3 打开浏览器，输入http://localhost:8889/，
lepd默认地址为www.rmlink.cn，点击右面的button按钮，

2.4 浏览器打开一个新标签页，输入http://localhost:8889/，
将lepd默认地址改为本机地址192.168.20.200，点击右面的button按钮，

反复实验，发现在CPU STAT结果出来之后，lepd才会段错误。
2.5 重复实验
因lepd已经退出，所以重新运行lepd
打开2.3的标签页，按F5刷新，点击右面的button按钮，待结果出来后，打开2.4的标签页，按F5刷新，点击右面的button按钮，待结果出来后，dmesg,发现lepd已经段错误。
重复实验，每次都能复现。
2.6 把main函数的//daemon(0, 1);注释掉，编译时加上-g选项，用gdb 运行lepd。
出现段错误后输入where,见下图：

echo "{"method":"GetProcMeminfo"}" | nc 10.10.10.145 12307
{
"error": {
"code": -32700,
"message": "Parse error. Invalid JSON was received by the server."
}
}

echo -n '{"method":"GetProcMeminfo"}' | nc 10.10.10.145 12307
{
"result": "MemTotal: 6103108 kB\nMemFree: 5172292 kB\nMemAvailable: 5195256 kB\nBuffers: 2080 kB\nCached: 78108 kB\nSwapCached:

browser connects lepd running on arm device with lepv, first time, got the data properly, second time, got 0 return.

log in arm:
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.592 MB perf.data (8050 samples) ]
run_cmd:size 0:perf record -a -e cpu-clock sleep 1

get_xxxid_info: Bad file descriptor
or
get_xxxid_info: Socket operation on non-socket

lepd forks a perf process when receiving a request from lepv, we need to integrate it into lepd like others

i stepped in with gdb, found something wrong in strjoin:

Program terminated with signal SIGABRT, Aborted.
#0 0x00007ffff7323428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
54 ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0 0x00007ffff7323428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007ffff732502a in __GI_abort () at abort.c:89
#2 0x00007ffff736b2e8 in __malloc_assert (assertion=assertion@entry=0x7ffff747f398 "(unsigned long) (size) >= (unsigned long) (nb)", file=file@entry=0x7ffff747bb85 "malloc.c",
line=line@entry=3722, function=function@entry=0x7ffff747f9a8 <func.11733> "_int_malloc") at malloc.c:301
#3 0x00007ffff73709b3 in _int_malloc (av=av@entry=0x7ffff76b2b20 <main_arena>, bytes=bytes@entry=13) at malloc.c:3722
#4 0x00007ffff7372184 in __GI___libc_malloc (bytes=13) at malloc.c:2913
#5 0x0000000000408dfe in strjoin (x=0x43f330 "/") at src/cgtop.c:63
#6 0x0000000000409fc4 in cg_read_subgroup (controller=0x43f384 "cpuacct", path=0x43f330 "/", iteration=0, depth=0, d=0x92ea20) at src/cgtop.c:474
#7 0x0000000000409ed5 in refresh_one (controller=0x43f384 "cpuacct", path=0x43f330 "/", iteration=0, depth=0) at src/cgtop.c:446
#8 0x000000000040a083 in refresh (iteration=0) at src/cgtop.c:498
#9 0x000000000040a5e7 in cgtop_main (argc=1, argv=0x7fffffffe240) at src/cgtop.c:616
#10 0x00000000004081de in run_builtin_cmd (ctx=0x7fffffffe3a0, params=0x0, id=0x0) at /root/lepd/src/server.c:206
#11 0x000000000040465a in invoke_procedure (server=0x673940 <my_server>, conn=0x69d3d0, name=0x69d550 "GetCmdCgtop", params=0x0, id=0x0) at /root/lepd/src/jsonrpc-c.c:87
#12 0x000000000040482f in eval_request (server=0x673940 <my_server>, conn=0x69d3d0, root=0x69d4c0) at /root/lepd/src/jsonrpc-c.c:122
#13 0x0000000000404af3 in connection_cb (loop=0x7ffff7dd68e0, w=0x69d3d0, revents=1) at /root/lepd/src/jsonrpc-c.c:180
#14 0x00007ffff7bccd73 in ev_invoke_pending () from /usr/lib/x86_64-linux-gnu/libev.so.4
#15 0x00007ffff7bd03de in ev_run () from /usr/lib/x86_64-linux-gnu/libe