Mailing List Archive: [mod_backhand-users] Graceful

[mod_backhand-users] Graceful

Sep 24, 2001, 1:04 AM

Post #1 of 4 (1121 views)

Hi,

A few days ago I reported some Problems with the use of a graceful restart.
Here is the requested strace:

scv03 /home/seuf# strace -p 1987
brk(0x87d8000) = 0x87d8000
brk(0x87db000) = 0x87db000
brk(0x87de000) = 0x87de000
brk(0x87e1000) = 0x87e1000
stat("/usr/local/httpd/htdocs/MoneySMSSend.asp", 0xbfff3ccc) = -1 ENOENT (No
such file or directory)
stat("/usr/local/httpd/htdocs", {st_mode=S_IFDIR|0755, st_size=4096, ...}) =
0
stat("/MoneySMSSend.asp", 0xbfff458c) = -1 ENOENT (No such file or
directory)
gettimeofday({1001316877, 758810}, NULL) = 0
write(8, "\0\324T@\22", 5) = -1 EPIPE (Broken pipe)
--- SIGPIPE (Broken pipe) ---
brk(0x87e4000) = 0x87e4000
brk(0x87e7000) = 0x87e7000
brk(0x87ea000) = 0x87ea000
brk(0x87ed000) = 0x87ed000
brk(0x87f0000) = 0x87f0000
brk(0x87f3000) = 0x87f3000
brk(0x87f6000) = 0x87f6000
brk(0x87f9000) = 0x87f9000
brk(0x87fc000) = 0x87fc000
brk(0x87ff000) = 0x87ff000
brk(0x8802000) = 0x8802000
brk(0x8805000) = 0x8805000
brk(0x8808000) = 0x8808000
stat("/usr/local/httpd/htdocs/MoneySMSSend.asp", 0xbfff3b6c) = -1 ENOENT (No
such file or directory)
stat("/usr/local/httpd/htdocs", {st_mode=S_IFDIR|0755, st_size=4096, ...}) =
0
stat("/MoneySMSSend.asp", 0xbfff442c) = -1 ENOENT (No such file or
directory)
gettimeofday({1001316878, 584906}, NULL) = 0
write(8, "\0\324T@\22", 5) = -1 EPIPE (Broken pipe)
--- SIGPIPE (Broken pipe) ---
brk(0x880b000) = 0x880b000
brk(0x880e000) = 0x880e000
brk(0x8811000) = 0x8811000
brk(0x8814000) = 0x8814000
brk(0x8817000) = 0x8817000
brk(0x881a000) = 0x881a000
brk(0x881d000) = 0x881d000
brk(0x8820000) = 0x8820000
brk(0x8823000) = 0x8823000
brk(0x8826000) = 0x8826000
brk(0x8829000) = 0x8829000
brk(0x882c000) = 0x882c000
brk(0x882f000) = 0x882f000
brk(0x8832000) = 0x8832000
stat("/usr/local/httpd/htdocs/MoneySMSSend.asp", 0xbfff3a0c) = -1 ENOENT (No
such file or directory)
stat("/usr/local/httpd/htdocs", {st_mode=S_IFDIR|0755, st_size=4096, ...}) =
0
stat("/MoneySMSSend.asp", 0xbfff42cc) = -1 ENOENT (No such file or
directory)
gettimeofday({1001316879, 356257}, NULL) = 0
write(8, "\0\324T@\22", 5) = -1 EPIPE (Broken pipe)
--- SIGPIPE (Broken pipe) ---
brk(0x8835000) = 0x8835000
brk(0x8838000) = 0x8838000

[...continues endless...]

A quick grep showed that mod_backhand doesn't contain much code which could
cause this while if caught some suspicious lines in mod_gzip... Maybe you
still have an idea as an experienced apache developer...

Thanks,

Stefan

[mod_backhand-users] Graceful [ In reply to ]

jesus at omniti

Sep 24, 2001, 8:27 PM

Post #2 of 4 (1086 views)

Permalink

On Monday, September 24, 2001, at 04:04 AM, Seufert, Stefan wrote:
> A few days ago I reported some Problems with the use of a graceful
> restart.
> Here is the requested strace:
>
> scv03 /home/seuf# strace -p 1987
> stat("/usr/local/httpd/htdocs/MoneySMSSend.asp", 0xbfff3ccc) = -1
> ENOENT (No
> such file or directory)
> stat("/usr/local/httpd/htdocs", {st_mode=S_IFDIR|0755,
> st_size=4096, ...}) =
> 0
> stat("/MoneySMSSend.asp", 0xbfff458c) = -1 ENOENT (No such file or
> directory)

The stat()ing of /MoneySMSSend.asp is not good. Kevin Walters alerted
me to this problem and I have a proposed fix in CVS for that. It should
at least save on stat(), but I think it will but the stat()s will be cut
in half. Feel free to check it out and see if it works for you :-)

> A quick grep showed that mod_backhand doesn't contain much code which
> could
> cause this while if caught some suspicious lines in mod_gzip... Maybe
> you
> still have an idea as an experienced apache developer...

Yeah. I don't see how mod_backhand would make your processes spin...

--
Theo Schlossnagle
1024D/82844984/95FD 30F1 489E 4613 F22E 491A 7E88 364C 8284 4984
2047R/33131B65/71 F7 95 64 49 76 5D BA 3D 90 B9 9F BE 27 24 E7

[mod_backhand-users] Graceful [ In reply to ]

se at fast-connect

Sep 25, 2001, 2:26 AM

Post #3 of 4 (1089 views)

Permalink

> On Monday, September 24, 2001, at 04:04 AM, Seufert, Stefan wrote:
> > A few days ago I reported some Problems with the use of a graceful
> > restart. Here is the requested strace:
> >
> > stat("/MoneySMSSend.asp", 0xbfff458c) = -1 ENOENT (No such file or
> > directory)
>
> The stat()ing of /MoneySMSSend.asp is not good. Kevin
> Walters alerted me to this problem and I have a proposed fix in
> CVS for that. It should at least save on stat(), but I think it will
> but the stat()s will be cut in half. Feel free to check it out and
> see if it works for you :-)
>
> [...]
>
> Yeah. I don't see how mod_backhand would make your processes spin...

I think the real problem seems to be the SIGPIPE occuring. After not being
able to write to the pipe (which pipe? a socket?) the client should die
intstead of retrying the whole procedure. Is this correct?

Stefan

[mod_backhand-users] Graceful [ In reply to ]

jesus at omniti

Sep 25, 2001, 7:24 AM

Post #4 of 4 (1098 views)

Permalink

On Tuesday, September 25, 2001, at 05:26 AM, Seufert, Stefan wrote:
> I think the real problem seems to be the SIGPIPE occuring. After not
> being
> able to write to the pipe (which pipe? a socket?) the client should die
> intstead of retrying the whole procedure. Is this correct?

Of course. My comment was a side note. the SIGPIPE does look like the
problem and I don't see how mod_backhand would be handling that
incorrectly.

--
Theo Schlossnagle
1024D/82844984/95FD 30F1 489E 4613 F22E 491A 7E88 364C 8284 4984
2047R/33131B65/71 F7 95 64 49 76 5D BA 3D 90 B9 9F BE 27 24 E7