Date: Mon, 27 Jul 1998 17:14:08 -0500 From: Karl Denninger <karl@mcs.net> To: Matt Dillon <dillon@best.net> Cc: Terry Lambert <tlambert@primenet.com>, Mike Smith <mike@smith.net.au>, wollman@khavrinen.lcs.mit.edu, current@FreeBSD.ORG Subject: Re: demonstration of mmap problem Message-ID: <19980727171408.52273@mcs.net> In-Reply-To: <199807272211.PAA05424@flea.best.net>; from Matt Dillon on Mon, Jul 27, 1998 at 03:11:46PM -0700 References: <199807272211.PAA05424@flea.best.net>
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Yep. That's EXACTLY what I'm seeing here - frequently. -- -- Karl Denninger (karl@MCS.Net)| MCSNet - Serving Chicagoland and Wisconsin http://www.mcs.net/ | T1's from $600 monthly / All Lines K56Flex/DOV | NEW! Corporate ISDN Prices dropped by up to 50%! Voice: [+1 312 803-MCS1 x219]| EXCLUSIVE NEW FEATURE ON ALL PERSONAL ACCOUNTS Fax: [+1 312 803-4929] | *SPAMBLOCK* Technology now included at no cost On Mon, Jul 27, 1998 at 03:11:46PM -0700, Matt Dillon wrote: > (forward this to the freebsd lists if you want. I also submitted a > bug report to FreeBSD). > > I was able to catch it in the act, though I am not entirely sure when > the actual file corruption occured. > > The hexdump of the data file below demonstrates the corruption. Note > that it 'ends' at a page boundry. I was also able to ktrace the > diablo process that was responsible for writing to the file. Note > that it has no problem writing to the file and that some of the areas > to which it wrote real data got zero'd out by the corruption problem. > > There is another process, not shown... a dnewslink was simultaniously > mmap()ing the same file SHARED+RO and transfering (touching the page(s) > near the end of the file continuously) the articles to the diablo > reader running on the same box. > > -Matt > > 0002.1960 0a 20 20 20 20 20 73 6f 6d 65 68 6f 77 20 61 20 . somehow a > 0002.1970 73 61 70 6c 69 6e 67 0a 20 20 20 20 20 6f 6e 20 sapling. on > 0002.1980 74 68 69 73 20 62 65 64 72 6f 63 6b 20 6f 66 20 this bedrock of > 0002.1990 61 20 74 6f 6e 67 75 65 0a 0a 20 20 20 20 20 69 a tongue.. i > 0002.19a0 74 20 77 69 6c 6c 20 62 65 0a 20 20 20 20 20 61 t will be. a > 0002.19b0 73 20 79 6f 75 20 68 61 76 65 20 77 72 69 74 74 s you have writt > 0002.19c0 65 6e 0a 20 20 20 20 20 61 73 20 65 78 61 63 74 en. as exact > 0002.19d0 20 61 6e 64 20 6c 6f 76 65 6c 79 0a 20 20 20 20 and lovely. > 0002.19e0 20 61 73 20 61 6e 79 20 66 72 75 69 74 20 62 65 as any fruit be > 0002.19f0 61 72 69 6e 67 20 74 68 69 6e 67 0a 20 20 20 20 aring thing. > 0002.1a00 20 74 68 61 74 20 77 69 6c 6c 20 65 76 65 72 20 that will ever > 0002.1a10 6d 61 6b 65 20 61 20 73 6f 75 6e 64 0a 0a 0a 37 make a sound...7 > 0002.1a20 2d 32 37 2d 39 38 0a 64 63 6c 65 0a 0a 2d 2d 2d -27-98.dcle..--- > 0002.1a30 2d 2d 3d 3d 20 50 6f 73 74 65 64 20 76 69 61 20 --== Posted via > 0002.1a40 44 65 6a 61 20 4e 65 77 73 2c 20 54 68 65 20 4c Deja News, The L > 0002.1a50 65 61 64 65 72 20 69 6e 20 49 6e 74 65 72 6e 65 eader in Interne > 0002.1a60 74 20 44 69 73 63 75 73 73 69 6f 6e 20 3d 3d 2d t Discussion ==- > 0002.1a70 2d 2d 2d 2d 0a 68 74 74 70 3a 2f 2f 77 77 77 2e ----.http://www. > 0002.1a80 64 65 6a 61 6e 65 77 73 2e 63 6f 6d 2f 72 67 5f dejanews.com/rg_ > 0002.1a90 6d 6b 67 72 70 2e 78 70 20 20 20 43 72 65 61 74 mkgrp.xp Creat > 0002.1aa0 65 20 59 6f 75 72 20 4f 77 6e 20 46 72 65 65 20 e Your Own Free > 0002.1ab0 4d 65 6d 62 65 72 20 46 6f 72 75 6d 0a 00 00 00 Member Forum.... > 0002.1ac0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1ad0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1ae0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1af0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1b00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1b10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1b20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > ... > 0002.1f70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1f80 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1f90 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1fa0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1fb0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1fc0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1fd0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1fe0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.1ff0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0002.2000 69 74 64 2e 75 6d 69 63 68 2e 65 64 75 21 6e 65 itd.umich.edu!ne > 0002.2010 77 73 2d 70 65 65 72 2e 67 69 70 2e 6e 65 74 21 ws-peer.gip.net! > 0002.2020 6e 65 77 73 2e 67 73 6c 2e 6e 65 74 21 67 69 70 news.gsl.net!gip > 0002.2030 2e 6e 65 74 21 6e 65 77 73 66 65 65 64 2e 69 6e .net!newsfeed.in > 0002.2040 74 65 72 6e 65 74 6d 63 69 2e 63 6f 6d 21 32 30 ternetmci.com!20 > 0002.2050 34 2e 32 33 38 2e 31 32 30 2e 31 33 30 21 6e 65 4.238.120.130!ne > > > 8240 diablo 0.000120 CALL lseek(0xe,0,0x21abe,0,0) > 8240 diablo 0.000041 RET lseek 137918/0x21abe > 8240 diablo 0.000032 CALL write(0xe,0x2278c020,0x283) > 8240 diablo 0.000095 GIO fd 14 wrote 643 bytes > "Path: news3.best.com!news1.best.com!feed1.news.erols.com!howland.erols.net!newsfeed.internetmci.com!204.238.120.130!news-feeds.jump.net!nntp2.dejanews.com!nnrp1.dejanews.com!not\ > -for-mail > From: parsrise@my-dejanews.com > Newsgroups: ott.business.ads > Subject: Ottawa, Centretown Apartments For Rent > Date: Mon, 27 Jul 1998 20:48:59 GMT > Organization: Deja News - The Leader in Internet Discussion > Lines: 29 > Message-ID: <6pip3s$f5b$1@nnrp1.dejanews.com> > NNTP-Posting-Host: 192.58.194.87 > X-Article-Creation-Date: Mon Jul 27 20:48:59 1998 GMT > X-Http-User-Agent: Mozilla/3.04 (X11; I; HP-UX A.09.03 9000/712) > Xref: news3.best.com ott.business.ads:12900 > " > 8240 diablo 0.000038 RET write 643/0x283 > 8240 diablo 0.000065 CALL lseek(0xe,0,0,0,0x1) > 8240 diablo 0.000032 RET lseek 138561/0x21d41 > 8240 diablo 0.000030 CALL write(0xe,0x2278c020,0x291) > 8240 diablo 0.000060 GIO fd 14 wrote 657 bytes > ... > 8240 diablo 0.000046 CALL lseek(0xe,0,0,0,0x1) > 8240 diablo 0.000033 RET lseek 139218/0x21fd2 > ... > > 139264 is the 4K boundry > > > > 8240 diablo 0.000054 CALL lseek(0xe,0,0x21fd2,0,0) > 8240 diablo 0.000037 RET lseek 139218/0x21fd2 > 8240 diablo 0.000035 CALL write(0xe,0x2278c020,0x2d9) > 8240 diablo 0.000408 GIO fd 14 wrote 729 bytes > "Path: news3.best.com!news1.best.com!newsxfer3.itd.umich.edu!news-peer.gip.net!news.gsl.net!gip.net!newsfeed.internetmci.com!204.238.120.130!news-feeds.jump.net!nntp2.dejanews.co\ > m!nnrp1.dejanews.com!not-for-mail > From: elleinad@my-dejanews.com > Newsgroups: rec.arts.disney.parks > Subject: Re: Planning 4 days at WDW > Date: Mon, 27 Jul 1998 20:52:41 GMT > Organization: Deja News - The Leader in Internet Discussion > Lines: 30 > Message-ID: <6pipaq$f81$1@nnrp1.dejanews.com> > References: <1998072618171400.OAA06477@ladder03.news.aol.com> > NNTP-Posting-Host: 204.189.84.62 > X-Article-Creation-Date: Mon Jul 27 20:52:41 1998 GMT > X-Http-User-Agent: Mozilla/4.0 (compatible; MSIE 4.0; Windows 95) > Xref: news3.best.com rec.arts.disney.parks:187617 > " > 8240 diablo 0.000056 RET write 729/0x2d9 > > 8240 diablo 0.000052 CALL lseek(0xe,0,0,0,0x1) > 8240 diablo 0.000032 RET lseek 139947/0x222ab > 8240 diablo 0.000030 CALL write(0xe,0x2278c020,0x537) > 8240 diablo 0.000066 GIO fd 14 wrote 1335 bytes > " > Well, I'm 13, and these are some of my favorites: > > Magic Kingdom: Space Mountain, Alien Encounter, Splash Mountain, Big Thunder > Mountain Railroad, the Barnstormer (back seat ONLY!) ;-) Epcot: Honey, I > Shrunk the Audience, the Image Works, Innoventions, Wonders of Life, and the > ride at Norway. MGM Studios: Tower of Terror, Star Tours, Superstar > Television, 50's Prime Time Cafe'. (It's an attraction in itself!) Animal > Kingdom: Kilimanjaro Safaris, Countdown to Extinction, Legend of the Lion > King show, Tough to Be A Bug. Water Parks: SUMMIT PLUMMET, Slush Gusher, > Downhill Double Dipper, and the fun chute slide (kind of off to itself) at > Ski Patrol Training Camp. > > Have fun! > > In article <1998072618171400.OAA06477@ladder03.news.aol.com>, > megps@aol.com (MegPS) wrote: > > We are headed to WDW on sunday for 4 days, We will be staying at CS, and we > > have passes for all of the parks and water parks. We have two girls, 14 and16, > > who will probably be on their own for much of the time, can you suggest some > > things that they might want to do while they're there? Thanks much. > > > > > -- > Danielle > Danielle@searnet.com > TDC Keeper of Pegasus, Summit Plummet, > > -----== Posted via Deja News, The Leader in Internet Discussion ==----- > http://www.dejanews.com/rg_mkgrp.xp Create Your Own Free Member Forum > \0" > 8240 diablo 0.000046 RET write 1335/0x537 > 8240 diablo 0.000040 CALL lseek(0xe,0,0,0,0x1) > 8240 diablo 0.000029 RET lseek 141282/0x227e2 > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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