This is on 2.0. This is a very simple consistency check
of the cache directory. The assert is finding
that a fragment size estimate in the directory is greater
than the max possible. In 2.0 this is 256k. It doesn't
look like there is any code to prevent HTTP from passing
in a buffer larger than this, so perhaps that is what is
happening.
To test this find the lines:
if (length > TARGET_FRAG_SIZE && length < SHRINK_TARGET_FRAG_SIZE)
write_len = TARGET_FRAG_SIZE;
else
write_len = length;
And remove the second conditional:
if (length > TARGET_FRAG_SIZE)
write_len = TARGET_FRAG_SIZE;
else
write_len = length;
This presumes that you have a rational size header. If you header
is on the order of 200k then the problem might still occur.
To test both conditions take that assert from 693 and insert it
at CacheWrite.cc:792 after the dir_set_approx_size and pass it vc->dir.
This will verify that the size is correct when it is set in the directory.
Tell me how this works out and I'll try to formulate a patch.
john
On 8/11/2010 9:36 AM, Patrick McManus wrote:
> Hi all -
>
> I'm working on a trafficserver plugin - and if I spin my ~40 case test
> suite through TS repeatedly I can pretty easily reproduce the assert
> below. (It is not deterministic, sometimes it takes just a couple
> iterations, sometimes dozens.)
>
> Ts is 2.0.0 that I compiled myself in debug mode on 64 bit linux.
>
> I've run it through valgrind and haven't seen my plugin doing anything
> suspicious - but I cannot reproduce the assert without the plugin
> installed. The plugin does change the document size and content.
>
> Unfortuantely, I don't own the copyright on the plugin code, so I cannot
> post it in whole.
>
> Anyone have any thoughts on what I might be doing wrong, or if there is
> a caching problem related to adaptations that change document sizes?
>
> FATAL: CacheDir.cc:693: failed assert `(unsigned int) dir_approx_size(dir) <=
> (unsigned int) (MAX_FRAG_SIZE + sizeofDoc)`
> /home/mcmanus/ts/bin/traffic_server - STACK TRACE:
> /home/mcmanus/ts/bin/traffic_server(ink_fatal_va+0xcb)[0x7579bb]
> /home/mcmanus/ts/bin/traffic_server(ink_fatal+0xc7)[0x757aa5]
> /home/mcmanus/ts/bin/traffic_server(_ink_assert+0xdb)[0x756bff]
> /home/mcmanus/ts/bin/traffic_server(_Z13dir_overwriteP7INK_MD5P4PartP3DirS4_b+0x18d)[0x6e8838]
> /home/mcmanus/ts/bin/traffic_server(_ZN7CacheVC22openWriteCloseHeadDoneEiP5Event+0x189)[0x70a2d1]
> /home/mcmanus/ts/bin/traffic_server(_ZN12Continuation11handleEventEiPv+0x6c)[0x4f1c22]
> /home/mcmanus/ts/bin/traffic_server(_ZN12PartCallback12aggWriteDoneEiP5Event+0x137)[0x7055dd]
> /home/mcmanus/ts/bin/traffic_server(_ZN12Continuation11handleEventEiPv+0x6c)[0x4f1c22]
> /home/mcmanus/ts/bin/traffic_server(_ZN7EThread13process_eventEP5Eventi+0x131)[0x74e66f]
> /home/mcmanus/ts/bin/traffic_server(_ZN7EThread7executeEv+0x31e)[0x74eb12]
> /home/mcmanus/ts/bin/traffic_server[0x74d1c6]
> /lib/libpthread.so.0(+0x69ca)[0x7ffff7bc59ca]
> /lib/libc.so.6(clone+0x6d)[0x7ffff59aa6fd]
>
> Program received signal SIGABRT, Aborted.
> [Switching to Thread 0x7ffff46a3710 (LWP 24261)]
> 0x00007ffff58f7a75 in *__GI_raise (sig=<value optimized out>) at
> ../nptl/sysdeps/unix/sysv/linux/raise.c:64
> 64 ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.
> in ../nptl/sysdeps/unix/sysv/linux/raise.c
> (gdb) bt
> #0 0x00007ffff58f7a75 in *__GI_raise (sig=<value optimized out>) at
> ../nptl/sysdeps/unix/sysv/linux/raise.c:64
> #1 0x00007ffff58fb5c0 in *__GI_abort () at abort.c:92
> #2 0x00000000007578f0 in ink_die_die_die (retval=1) at ink_error.cc:43
> #3 0x00000000007579c8 in ink_fatal_va (return_code=1,
> message_format=0x7ffff46a29b0 "CacheDir.cc:693: failed assert `(unsigned
> int) dir_approx_size(dir) <= (unsigned int) (MAX_FRAG_SIZE + sizeofDoc)`",
> ap=0x7ffff46a28b0)
> at ink_error.cc:67
> #4 0x0000000000757aa5 in ink_fatal (return_code=1,
> message_format=0x7ffff46a29b0 "CacheDir.cc:693: failed assert `(unsigned
> int) dir_approx_size(dir) <= (unsigned int) (MAX_FRAG_SIZE + sizeofDoc)`") at
> ink_error.cc:75
> #5 0x0000000000756bff in _ink_assert (a=0x7ec9e0 "(unsigned int)
> dir_approx_size(dir) <= (unsigned int) (MAX_FRAG_SIZE + sizeofDoc)",
> f=0x7ec64c "CacheDir.cc", l=693)
> at ink_assert.cc:47
> #6 0x00000000006e8838 in dir_overwrite (key=0x1c21fe0, d=0x19d04d0,
> dir=0x1c22010, overwrite=0x1c370b8, must_overwrite=false) at CacheDir.cc:693
> #7 0x000000000070a2d1 in CacheVC::openWriteCloseHeadDone (this=0x1c21f90,
> event=3900, e=0x0) at CacheWrite.cc:1170
> #8 0x00000000004f1c22 in Continuation::handleEvent (this=0x1c21f90,
> event=3900, data=0x0) at ../iocore/eventsystem/I_Continuation.h:147
> #9 0x00000000007055dd in PartCallback::aggWriteDone (this=0x19cdda0,
> event=1, e=0x1bc95e0) at CacheWrite.cc:327
> #10 0x00000000004f1c22 in Continuation::handleEvent (this=0x19cdda0, event=1,
> data=0x1bc95e0) at ../iocore/eventsystem/I_Continuation.h:147
> #11 0x000000000074e66f in EThread::process_event (this=0x7ffff4aa8010,
> e=0x1bc95e0, calling_code=1) at UnixEThread.cc:113
> #12 0x000000000074eb12 in EThread::execute (this=0x7ffff4aa8010) at
> UnixEThread.cc:219
> #13 0x000000000074d1c6 in spawn_thread_internal (a=0xc090c0) at Thread.cc:85
> #14 0x00007ffff7bc59ca in start_thread (arg=<value optimized out>) at
> pthread_create.c:300
> #15 0x00007ffff59aa6fd in clone () at
> ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
> #16 0x0000000000000000 in ?? ()
> (gdb)
>
