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debug.txt
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debug.txt
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- strace
strace -o strace.txt -ttT -s 1024 -p `pgrep nutcracker`
- libyaml (yaml-0.2.5)
- yaml tokens:
0 YAML_NO_TOKEN,
1 YAML_STREAM_START_TOKEN,
2 YAML_STREAM_END_TOKEN,
3 YAML_VERSION_DIRECTIVE_TOKEN,
4 YAML_TAG_DIRECTIVE_TOKEN,
5 YAML_DOCUMENT_START_TOKEN,
6 YAML_DOCUMENT_END_TOKEN,
7 YAML_BLOCK_SEQUENCE_START_TOKEN,
8 YAML_BLOCK_MAPPING_START_TOKEN,
9 YAML_BLOCK_END_TOKEN,
10 YAML_FLOW_SEQUENCE_START_TOKEN,
11 YAML_FLOW_SEQUENCE_END_TOKEN,
12 YAML_FLOW_MAPPING_START_TOKEN,
13 YAML_FLOW_MAPPING_END_TOKEN,
14 YAML_BLOCK_ENTRY_TOKEN,
15 YAML_FLOW_ENTRY_TOKEN,
16 YAML_KEY_TOKEN,
17 YAML_VALUE_TOKEN,
18 YAML_ALIAS_TOKEN,
19 YAML_ANCHOR_TOKEN,
20 YAML_TAG_TOKEN,
21 YAML_SCALAR_TOKEN
- yaml events
0 YAML_NO_EVENT,
1 YAML_STREAM_START_EVENT,
2 YAML_STREAM_END_EVENT,
3 YAML_DOCUMENT_START_EVENT,
4 YAML_DOCUMENT_END_EVENT,
5 YAML_ALIAS_EVENT,
6 YAML_SCALAR_EVENT,
7 YAML_SEQUENCE_START_EVENT,
8 YAML_SEQUENCE_END_EVENT,
9 YAML_MAPPING_START_EVENT,
10 YAML_MAPPING_END_EVENT
- sys/queue.h
queue.h is a generic linked list library adapted from BSD. It has three
macro knobs that are useful for debugging:
- QUEUE_MACRO_SCRUB nullifies links (next and prev pointers) of deleted
elements and catches cases where we are attempting to do operations
on an element that has already been unlinked.
- QUEUE_MACRO_TRACE keeps track of __FILE__ and __LINE__ of last two
updates to the list data structure.
- QUEUE_MACRO_ASSERT verifies the sanity of list data structure on every
operation.
- valgrind
valgrind --tool=memcheck --leak-check=yes <program>
- Core dump
ulimit -c unlimited
- Generate ENOMEM to test "Out of Memory"
ulimit -m <size> # limit maximum memory size
ulimit -v <size> # limit virtual memory
- get nutcracker stats
printf "" | socat - TCP:localhost:22222 | tee stats.txt
printf "" | nc localhost 22222 | python -mjson.tool
- Signalling and Logging
SIGTTIN - To up the log level
SIGTTOU - To down the log level
SIGHUP - To reopen log file
- Error codes:
http://www.cs.utah.edu/dept/old/texinfo/glibc-manual-0.02/library_2.html
/usr/include/asm-generic/errno-base.h
/usr/include/asm-generic/errno.h
- epoll (linux)
union epoll_data {
void *ptr;
int fd;
uint32_t u32;
uint64_t u64;
};
struct epoll_event {
uint32_t events; /* epoll events */
struct epoll_data data; /* user data variable */
};
/* events */
EPOLLIN = 0x001,
EPOLLPRI = 0x002,
EPOLLOUT = 0x004,
EPOLLERR = 0x008,
EPOLLHUP = 0x010,
EPOLLRDNORM = 0x040,
EPOLLRDBAND = 0x080,
EPOLLWRNORM = 0x100,
EPOLLWRBAND = 0x200,
EPOLLMSG = 0x400,
EPOLLRDHUP = 0x2000,
EPOLLONESHOT = (1 << 30),
EPOLLET = (1 << 31)
/* opcodes */
EPOLL_CTL_ADD = 1 /* add a file descriptor to the interface */
EPOLL_CTL_DEL = 2 /* remove a file descriptor from the interface */
EPOLL_CTL_MOD = 3 /* change file descriptor epoll_event structure */
- kqueue (bsd)
struct kevent {
uintptr_t ident; /* identifier for this event */
int16_t filter; /* filter for event */
uint16_t flags; /* general flags */
uint32_t fflags; /* filter-specific flags */
intptr_t data; /* filter-specific data */
void *udata; /* opaque user data identifier */
};
/* flags / events */
EV_ADD = 0x0001 /* action - add event to kq (implies enable) */
EV_DELETE = 0x0002 /* action - delete event from kq */
EV_ENABLE = 0x0004 /* action - enable event */
EV_DISABLE = 0x0008 /* action - disable event (not reported) */
EV_RECEIPT = 0x0040 /* action - force EV_ERROR on success, data == 0 */
EV_ONESHOT = 0x0010 /* flags - only report one occurrence */
EV_CLEAR = 0x0020 /* flags - clear event state after reporting */
EV_DISPATCH = 0x0080 /* flags - disable event after reporting */
EV_SYSFLAGS = 0xF000 /* flags - reserved by system */
EV_FLAG0 = 0x1000 /* flags - filter-specific flag */
EV_FLAG1 = 0x2000 /* flags - filter-specific flag */
EV_EOF = 0x8000 /* returned values - EOF detected */
EV_ERROR = 0x4000 /* returned values - error, data contains errno */
/* filters */
EVFILT_READ (-1) /* readable */
EVFILT_WRITE (-2) /* writable */
EVFILT_AIO (-3) /* attached to aio requests */
EVFILT_VNODE (-4) /* attached to vnodes */
EVFILT_PROC (-5) /* attached to struct proc */
EVFILT_SIGNAL (-6) /* attached to struct proc */
EVFILT_TIMER (-7) /* timers */
EVFILT_MACHPORT (-8) /* mach portsets */
EVFILT_FS (-9) /* filesystem events */
EVFILT_USER (-10) /* user events */
EVFILT_VM (-12) /* virtual memory events */
EV_CLEAR behaves like EPOLLET because it resets the event after it is
returned; without this flag, the event would be repeatedly returned.
- poll (unix)
POLLIN 0x001 /* there is data to read */
POLLPRI 0x002 /* there is urgent data to read */
POLLOUT 0x004 /* writing now will not block */
POLLRDNORM 0x040 /* normal data may be read */
POLLRDBAND 0x080 /* priority data may be read */
POLLWRNORM 0x100 /* writing now will not block */
POLLWRBAND 0x200 /* priority data may be written */
POLLMSG 0x400
POLLREMOVE 0x1000
POLLRDHUP 0x2000
POLLERR 0x008 /* error condition */
POLLHUP 0x010 /* hung up */
POLLNVAL 0x020 /* invalid polling request */
- event ports (solaris)
typedef struct port_event {
int portev_events; /* event data is source specific */
ushort_t portev_source; /* event source */
ushort_t portev_pad; /* port internal use */
uintptr_t portev_object; /* source specific object */
void *portev_user; /* user cookie */
} port_event_t;
/* port sources */
PORT_SOURCE_AIO 1
PORT_SOURCE_TIMER 2
PORT_SOURCE_USER 3
PORT_SOURCE_FD 4
PORT_SOURCE_ALERT 5
PORT_SOURCE_MQ 6
PORT_SOURCE_FILE 7