问题一：
when I try to compile pTop I get the following message: cc -c -o src/avltree.o src/avltree.c In file included from src/avltree.c:12: src/eperf.h:
In function 'sys_perf_event_open':
src/eperf.h:32: error: '__NR_perf_counter_open' undeclared (first use in this function)
src/eperf.h:32: error: (Each undeclared identifier is reported only once src/eperf.h:32: error: for each function it appears in.)
make: *** [src/avltree.o] Erro
解决方法：
although the kernel version was above the required linux-headers were outdated.
Updating linux-headers to match the kernel version solved the issue.
Also had to rename the system call in pTop code, but this was already documented in the readme file.
具体做法：
1、yum update kernel-devel
2、查看 see the file "/usr/include/asm/unistd_32.h" or "/usr/include/asm/unistd_64.h".中有哪个system call
"__NR_perf_counter_open"(in the latest version, the name is "__NR_perf_event_open")
3、修改源代码中的系统调用
问题二：
找不到<mysql/mysql.h>
解决方法：
安装mysql的时候没有将头文件放入到/usr/include文件夹里。sudo cp -r /usr/local/mysql/include /usr/include/mysql
问题三：
error: /usr/bin/ld: cannot find -lmysqlclient
解决方法：
将mysql下的bin目录的所有文件拷贝到/usr/lib下
问题四：
运行的时候出错： error while loading shared libraries: libmysqlclient.so.18: cannot open shared object file: No such file or directory ===================================================
解决方法：
网上找到的解决办法是 ln -s /usr/local/mysql/lib/libmysqlclient.so.18 /usr/lib/ 照做后仍然报错，原因是该方法适用于32位系统，64位系统应使用下面的这行 ln -s /usr/local/mysql/lib/libmysqlclient.so.18 /usr/lib64/ 另外：在编译的时候，不写mysql的路径，而使用mysqlnd代替，也可解决该问题的出现。