On Wed, Apr 16, 2008 at 12:19:35PM -0700, mobigital1 wrote:

I tried replacing the {prefix} and also just changing specific variables in monetdb5.conf that reference {prefix}....

the latest thing I tried is replacing /var/monetdb/var with a new mount to a larger disk. I formatted the disk as NFTS - it mounts fine, but monetdb crashes.

I believe I had imported the same data before into an originally built installation and it imported ok. I think had around 200M rows there.

completely buffled why this is crashing now. I have rebuilt monetdb from the tarball - it kept crashing.

I am running Fedora 8 64 bit edition with 32GB ram.

Does it care what is the filesystem type of share on which dbfarm lives?

Can someone give some guidance on what is a working configuration? nothing seems to make monetdb happy!!!!

Example which works here. gdk_dbfarm=/scratch/var/MonetDB5/dbfarm sql_logdir=/scratch/var/MonetDB5/sql_logs Else could you include your current (anonymized) monetdb5.conf Niels

Niels Nes wrote:

...

On Tue, Apr 15, 2008 at 07:34:06PM -0700, mobigital1 wrote:

...

i am trying to setup the dbfarm location to be on a different share from /opt/monetdb/var directory. i modified the /opt/monetdb/etc/monetdb5.conf file to reflect the alternate path to dbfarm location, and also sql-log location.

Where do the point to now, ie you only replaced the prefix /opt/monetdb/var by you new partition?

Niels

...

...

...

merogivian start <dbname> but it is very unstable and crashes when i try to import some data. I have been able to import the same data when dbfarm was under /opt/monetdb/var

i am able to start the server with directory. is there something else I need to do to relocate dbfarm to another folder? the new folder is mounted to another disk. (ext3 partition)

...

any advice would be appreciated.

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On Wed, Apr 16, 2008 at 12:38:45PM -0700, mobigital1 wrote:

I am sure I have tried the change below. In addition to that I had mapi_open set to true, and mapi_port set to 5000, also tried 50000. could port cause instability?

All of your changes shouldn't cause instability at all. The only thing which could cause this is only changing the dbfarm and not the log directory (or vice versa). This would possibly give a inconsistent db, leading to crashes.

I am testing a fresh build/install now will see how it works.

recreated db partition as Linux, formatted as mkfs -t ext3

Niels

Niels Nes wrote:

...

On Wed, Apr 16, 2008 at 12:19:35PM -0700, mobigital1 wrote:

...

I tried replacing the {prefix} and also just changing specific variables in monetdb5.conf that reference {prefix}....

...

the latest thing I tried is replacing /var/monetdb/var with a new mount to a larger disk. I formatted the disk as NFTS - it mounts fine, but monetdb crashes.

I believe I had imported the same data before into an originally built installation and it imported ok. I think had around 200M rows there.

completely buffled why this is crashing now. I have rebuilt monetdb from the tarball - it kept crashing.

I am running Fedora 8 64 bit edition with 32GB ram.

Does it care what is the filesystem type of share on which dbfarm lives?

Can someone give some guidance on what is a working configuration? nothing seems to make monetdb happy!!!!

Example which works here.

gdk_dbfarm=/scratch/var/MonetDB5/dbfarm sql_logdir=/scratch/var/MonetDB5/sql_logs

Else could you include your current (anonymized) monetdb5.conf

Niels

...

Niels Nes wrote:

...

On Tue, Apr 15, 2008 at 07:34:06PM -0700, mobigital1 wrote:

...

i am trying to setup the dbfarm location to be on a different share

from

...

...

/opt/monetdb/var directory. i modified the /opt/monetdb/etc/monetdb5.conf file to reflect the alternate path to dbfarm location, and also sql-log location. Where do the point to now, ie you only replaced the prefix /opt/monetdb/var by you new partition?

Niels

...

i am able to start the server with

...

> merogivian start <dbname> but it is very unstable and crashes when i try to import some data. I have been able to import the same data when dbfarm was under

/opt/monetdb/var

...

directory. is there something else I need to do to relocate dbfarm to another folder? the new folder is mounted to another disk. (ext3 partition)

...

any advice would be appreciated.

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Example which works here. gdk_dbfarm=/scratch/var/MonetDB5/dbfarm sql_logdir=/scratch/var/MonetDB5/sql_logs

Else could you include your current (anonymized) monetdb5.conf

Niels

I tried the above example switching like this: gdk_dbfarm=/data/MonetDB5/dbfarm sql_logdir=/data/MonetDB5/sql_logs left everything else unchanged in the log file. 1. merovigian starts ok. does not complain in log about anything 2. database starts ok, i see mserver5 running. when I try connecting to client it says "database does not accept connections" NOTE: my monetdb5.conf says mapi_open=false, however, the ps shows that mserver5 is running with -set mapi open true. ?? how come? -- View this message in context: http://www.nabble.com/alternate-dbfarm-location-not-working-tp16715294p16744... Sent from the monetdb-users mailing list archive at Nabble.com.

That's ok when we have a large database, but I was trying this with a blank database right after switching the dbfarm location to /data/MonetDB5 when I pointed back to the original config file, and started it up, i was able to connect right away, but after one \q and reconnect got a credentials issue. so at that point (while back in original configuration), I destroyed the database and recreated it. then connecting worked fine. so there are 2 issues: 1. monetdb does not support changing the dbfarm location 2. monetdb does not support moving the database to another location. something was not working when db files were moved ... could this be because of some issue in memory -mapped files? may be kernel had some references to these files by their old locations? Fabian Groffen wrote:

On 17-04-2008 06:29:08 -0700, mobigital1 wrote:

...

...

Example which works here. gdk_dbfarm=/scratch/var/MonetDB5/dbfarm sql_logdir=/scratch/var/MonetDB5/sql_logs

Else could you include your current (anonymized) monetdb5.conf

Niels

I tried the above example switching like this:

gdk_dbfarm=/data/MonetDB5/dbfarm sql_logdir=/data/MonetDB5/sql_logs

left everything else unchanged in the log file.

1. merovigian starts ok. does not complain in log about anything 2. database starts ok, i see mserver5 running.

when I try connecting to client it says "database does not accept connections"

That means the sql module has not finished starting (yet).

...

NOTE: my monetdb5.conf says mapi_open=false, however, the ps shows that mserver5 is running with -set mapi open true. ?? how come?

Merovingian overrides this because otherwise redirection won't work. The next version of Merovingian will make this not any more necessary.

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On Thu, Apr 17, 2008 at 06:29:08AM -0700, mobigital1 wrote:

...

Example which works here. gdk_dbfarm=/scratch/var/MonetDB5/dbfarm sql_logdir=/scratch/var/MonetDB5/sql_logs

Else could you include your current (anonymized) monetdb5.conf

Niels

I tried the above example switching like this:

gdk_dbfarm=/data/MonetDB5/dbfarm sql_logdir=/data/MonetDB5/sql_logs

left everything else unchanged in the log file.

1. merovigian starts ok. does not complain in log about anything 2. database starts ok, i see mserver5 running.

when I try connecting to client it says "database does not accept connections"

NOTE: my monetdb5.conf says mapi_open=false, however, the ps shows that mserver5 is running with -set mapi open true. ?? how come?

mapi_open=true is needed when you connect from a different machine or when you machine doesn't have a correct localhost network setup. So start with mserver5 --dbinit="include sql;" --set mapi_open=true Niels

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On Wed, Apr 16, 2008 at 03:07:05PM -0700, mobigital1 wrote:

is it possible to purge the sql_log directory contents? it has grown to around 100gb right now, not sure if it's there to stay forever or can i run some command to compact/delete it?

How did you manage to get 100GB log files. Did you create many different db's or is this for a single database. The file 'log' in the directory sql_logs/'database'/ describes which log files are still needed. This file consists of a version number, empty line, then the list of log file numbers. So any number lower could be removed (and should have been). Niels

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On Thu, Apr 17, 2008 at 03:12:13PM -0700, mobigital1 wrote:

Below is the configuration that would not work with a blank database. the error was that database is not accepting connections.

Okay that started correctly and didn't crash then. The connection problem was explained by fabian. The clean server uses a by merovingian placed vault_key file (see you monet_vault_key variable down). If you remove it or replace the variable to point somewere else it should work. Niels Fabian: could you explain why monetdb login does fail in that case?

# Configuration file for MonetDB Version 5 server

# The configuration file is an integral part of a database store # and aimed to initialize the server and service components. # This startup file is read by the GDK kernel to set system wide parameters.

# It may be inspected by application/scripts for specific settings, # but such client side configurations are better packed in their # own structure.

# It can also reside in the local directory # where mserver is called, or the home directory of the MonetDB user.

# Absolute path where MonetDB is installed prefix=/opt/monetdb exec_prefix=${prefix}

# GDK Section #============ # All databases are stored as a directory under the directory # given below. Use this value to change the overall location # of your data. gdk_dbfarm=/data/MonetDB5/dbfarm

# MonetDB can only handle one database at a time. When you start an # mserver5 manually without specifying the database name yourself, the # following database name is used. gdk_dbname=demo

# The options below deal with various aspects of memory usage behaviour. # If you don't know what these values mean, you should leave them alone.

# gdk_mem_bigsize & gdk_vm_minsize will be set/limited to # 1/2 of the physically available amount of main-memory # during start-up in src/tools/mserver.mx # memory chunks of size >= gdk_mem_bigsize (in bytes) will be mmaped anonymously #gdk_mem_bigsize=262144 # memory chunks of size >= gdk_vm_minsize (in bytes) will be mmaped; #gdk_vm_minsize=137438953472 # for 32 bit systems try to claim 3G of (virtual) memory; #gdk_vmtrim=yes # set to "no" to disable the vmtrim thread.

# valgrind issues: # for 32 bit systems it tries claim 3G of (virtual) memory # set the alloca map to "no" to run mserver with valgrind; # also, you need to tell valgrind to use 8-byte alignment, hence: # "valgrind --alignment=8 mserver --set gdk_alloc_map=no ..." gdk_alloc_map=no

# the kernel can be used in embedded situations (don't set this yourself) gdk_embedded=no

# You can enable debug for specific parts. By default debug is # switched off. gdk_debug=0 # possible values: (can be a combination of) # 1 = thread-specific debug output # 2 = CHECKMASK = property enforcing on new BATs # 4 = MEMMASK = memory allocation # 8 = PROPMASK = property checking on all values: tells about # wrongly set properties # 16 = IOMASK = major IO activity # 32 = BATMASK = BAT handling # 64 = PARSEMASK = parser debugging # 128 = PARMASK = Thread management # 256 = TRGMASK = Event management # 512 = TMMASK = Transaction management # 1024 = TEMMASK = Locks and Triggers # 2048 = DLMASK = Dynamic loading # 4096 = PERFMASK = BBP Performance (?) # 8192 = DELTAMASK = Delta debugging (?) # 16384 = LOADMASK = Module loading # 32768 = YACCMASK = Yacc specific error messages # 65536 = obsolete = tcpip (??) # 131072 = obsolete = monet_multiplex: setaggr debugging (??) # 262144 = obsolete = \ # 524288 = obsolete = ddbench (???) # 1048576 = obsolete = / # 2097152 = ALGOMASK = show join/select algorithm chosen # 4194304 = ESTIMASK = show result size estimations (for join,select) # 8388608 = XPROPMASK = extended property checking: tells also about # not set properties #16777216 = JOINPROPMASK = disable property checking with join & outerjoin # (e.g., for performance measurements) #33554432 = DEADBEEFMASK = disable "cleaning" of freed memory in GDKfree() # (e.g., for performance measurements) # # Mserver 5 recognizes a series of command line names instead: # --threads ( 1 | PARMASK) # --memory (MEMMASK ) # --properties (CHECKMASK | PROPMASK | BATMASK ) # --io (IOMASK | PERFMASK ) # --transactions ( TMMASK | DELTAMASK | TEMMASK) # --modules (DLMASK | LOADMASK) # --algorithms (ALGOMASK | ESTIMASK) # --xproperties (XPROPMASK ) # --performance (JOINPROPMASK | DEADBEEFMASK)

# Monet Section #============== # monet_admin=adm #administrator user name # Prompt when using MAL interface # monet_prompt=> # Where do the MonetDB modules reside? The second path is for windows dlls. monet_mod_path=${exec_prefix}/lib/MonetDB5:${exec_prefix}/lib/MonetDB5/lib:${exec_prefix}/lib/MonetDB5/bin # Start mserver in daemon mode, or start with MAL interactive interface? monet_daemon=no # Display version and copyright information upon startup? monet_welcome=yes # Where is the file that stores the secret key to unlock the password # vault? The file is read up to the first null-byte ('\0'), so you can # padd the file with trailing null-bytes to obfuscate the key length. # You can easily generate some key by running pwgen and adding a few of # the passwords generated. Make sure not to make the key too small. # If you leave this unset, some default key is used. # If you use Merovingian, a per-database vault key is used and this # setting ignored. #monet_vault_key=${prefix}/etc/monetdb.secret

# Merovingian section #==================================== # Merovingian logs messages and errors by default to the stdout and # stderr channels on the console. By setting one or both of the # variables below, one can specify messages and/or errors to be logged # to a file instead. It is legitimate to have both mero_msglog and # mero_errlog pointing to the same file, as in the default below. # Unsetting below defaults will make merovingian log to the screen. mero_msglog=${prefix}/var/log/merovingian.log mero_errlog=${prefix}/var/log/merovingian.log # # Log messages may not be instantly logged, because the process that # writes the message does not flush its buffered stream. Since # Merovingian cannot force other processes to flush their output, the # time when Merovingian receives the message need not to be (close) to # the actual time the message was generated. For this reason it makes # not much sense to tag each line with the time it is printed by # Merovingian. Instead, Merovingian does a rough time indication by # inserting TME records in the log output. The seconds interval in # which Merovingian should print such TME record can be specified below. # Note that an interval of 0 makes Merovingian print a TME record for # every printed log record. The default is to print a TME record every # 10 minutes. mero_timeinterval=600 # # Merovingian forks itself to detach into the background. It stores its # pid in the following file, which can be used to stop Merovingian # again. mero_pidfile=${prefix}/var/run/merovingian.pid # # In normal use, Merovingian replaces an mserver, and hence listens for # connections on the same port as an mserver would do. For certain # configs, however, it may be more suitable to use an alternate port, # which can be specified here. #mero_port=50000 # # mservers that were started by Merovingian are shut down when the # Merovingian is shut down. This behaviour is desirable if the # Merovingian is ran as daemon process that represents MonetDB, such as # in an init.d script. Setting the time-out value below to a positive # non-zero value will shut down each mserver that was started with a # given time-out in seconds. If the time-out expires, the mserver is # killed using the SIGKILL signal. A time-out value of 0 means that no # mserver is shut down, meaning they will live on after the Merovingian # has shut down. The default is to shut down all started mservers with # a time-out of 7 seconds. mero_exittimeout=7

# MAL section # Monet Virtual Machine #==================================== mal_init=${exec_prefix}/lib/MonetDB5/mal_init.mal mal_listing = 15 # List everything # 1 = List the original input # 2 = List the MAL instruction # 4 = List the MAL type information # 8 = List the MAL properties

# Checkpoint and recovery #=================================== # Checkpoints are stored in their own area, preferrably # on a different storage device. Checkpoints should be # initialized manually. checkpoint_dir=${prefix}/var/MonetDB5/chkpnt

# Monet Application Interface Section #==================================== mapi_port=50000 # default port to address a mserver mapi_open=true # should be set to 'true' to allow for # remote access to a server

# SQL Interface Section #==================================== # The SQL debug level (should be disabled for normal use) sql_debug=0

# Place to store transaction logs # The logs are typically stored on a different storage medium # to protect the database against accidental hardware loss. sql_logdir=/data/MonetDB5/sql_logs

# The sql_init is a comma separated list of sql files to be # executed upon system restart. It is primarily used to make # SQL library functions known to all users. sql_init=${exec_prefix}/lib/MonetDB5/sql_init.sql

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