What OS are you running ? Linux(32 or 64 Bit)? Ext 3 Filesystem ? Wich Kernel Version ? Bug in Ext 3/Linux Kernel/Hardware(Raid Controller ?) ? Does the error only happens under heavy load ? regards, -Franz -----Ursprüngliche Nachricht----- Von: pgsql-general-owner@xxxxxxxxxxxxxx [mailto:pgsql-general-owner@xxxxxxxxxxxxxx] Im Auftrag von Paolo Bizzarri Gesendet: Samstag, 2. Juni 2007 07:46 An: Purusothaman A Cc: Richard Huxton; pgsql-general@xxxxxxxxxxxxxx Betreff: Re: [GENERAL] Corruption of files in PostgreSQL Hi everyone, a little update. We have upgraded our system to 7.4.17. The problem of truncated files seems now better, but it is still present. We have not found a clearly understandable pattern on why this happens. Just to provide some further information: - we create a file and store on the DB; - we give the file to the user, and he can modify at its wish the file; - we store back the modified file on the DB; - the last two points can happen several times. Any hint? Best regards. Paolo Bizzarri Icube S.r.l. On 5/30/07, Purusothaman A <purusothaman.a@xxxxxxxxx> wrote: > Paolo Bizzarri, > > I am also using postgresql in my application and also facing file object > corruption problem. > > I already discussed several times with Richard Huxton, and ended without any > clue. > > Here I am briefing my problem, see if u find any clue about it. > I am storing/retrieving my file in postgresql using lo_export() and > lo_import() api. > > after few weeks (as application is being used - number of file objects in > database also grows) my file object gets corrupted. And I have no clue about > which causes this problem. > > I confirmed the file corruption by the following query, > > sfrs2=> select loid, pageno, length(data) from pg_largeobject where loid = > 101177 and pageno = 630; > loid | pageno | length > --------+--------+-------- > 101177 | 630 | 181 > (1 row) > > But actually the result of the above query before corruption(ie, immediately > after file object added to table) > > fasp_test=> select loid, pageno, length(data) from pg_largeobject where loid > = 106310 and pageno = 630; > loid | pageno | length > --------+--------+-------- > 106310 | 630 | 205 > (1 row) > > I uploaded same file in both(sfrs2, fasp_test) databases. The first one > result is after the corruption. and the later is before corruption. > > You also confirm you problem like this. And I strongly believe that, there > is some bug in PostgreSQL. > > Kindly don't forget to alert me once u find solution/cause. > > Regards, > Purusothaman A > > > On 5/30/07, Paolo Bizzarri <pibizza@xxxxxxxxx> wrote: > > > > On 5/30/07, Richard Huxton <dev@xxxxxxxxxxxx> wrote: > > > Paolo Bizzarri wrote: > > > > We use postgres as a backend, and we are experimenting some corruption > > > > problems on openoffice files. > > > > > > 1. How are you storing these files? > > > > Files are stored as large objects. They are written with an lo_write > > and its contents is passed as a Binary object. > > > > > 2. What is the nature of the corruption? > > > > Apparently, files get truncated. > > > > > > As our application is rather complex (it includes Zope as an > > > > application server, OpenOffice as a document server and as a client) > > > > we need some info on how to check that we are interacting correctly > > > > with Postgres. > > > > > > Shouldn't matter. > > > > I hope so... > > > > > > We are currently using: > > > > > > > > - PostgreSQL 7.4.8; > > > > > > Well, you need to upgrade this - version 7.4.17 is the latest in the 7.4 > > > series. You are missing 9 separate batches of bug and security fixes. > > > > Ok. We will upgrade and see if this can help solve the problem. > > > > > > > > > - pyscopg 1.1.11 ; > > > > - Zope 2.7.x; > > > > - Openoffice 2.2. > > > > > > None of this should matter really, unless there's some subtle bug in > > > psycopg causing corruption of data in-transit. > > > > > > Let's get some details on the two questions above and see if there's a > > > pattern to your problems. > > > > Ok. Thank you. > > > > Paolo Bizzarri > > Icube S.r.l. > > > > ---------------------------(end of > broadcast)--------------------------- > > TIP 5: don't forget to increase your free space map settings > > > > > > -- > http://PurusothamanA.wordpress.com/ ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
