Обсуждение: out of memory - no sort
I am trying a simple
access of a table and get an out of
memory error. How do I avoid this issue. It seems I
have some configuration set wrong.
Our system has 24GB of memory and is dedicated to the postgres
database.
Back ground information
aquarec=> explain analyze verbose select * from ens_memb;
QUERY
PLAN
--------------------------------------------------------------------------------------------------------------------------
Seq Scan on ens_memb (cost=0.00..719893.12 rows=32216212
width=62) (actual time=4.954..37513.377 rows=32216154 loops=1)
Output: id, shefpc, bwmon, ewmon, pb, tb, cdate, vdate,
source, tyr, val
Total runtime: 39588.386 ms
#------------------------------------------------------------------------------
# RESOURCE USAGE (except WAL)
#------------------------------------------------------------------------------
# - Memory -
shared_buffers =
6144MB # min 128kB
#(change requires
restart)
#temp_buffers =
8MB
#min 800kB
max_prepared_transactions = 5 # zero disables the
feature
#(change requires
restart)
# Note: Increasing max_prepared_transactions costs ~600 bytes
of shared memory
# per transaction slot, plus lock space (see
max_locks_per_transaction).
# It is not advisable to set max_prepared_transactions nonzero
unless you
# actively intend to use prepared transactions.
work_mem =
48MB
#min 64kB
maintenance_work_mem = 256MB # min 1MB
#max_stack_depth =
2MB # min 100kB
# - Kernel Resource Usage -
#max_files_per_process = 1000 # min 25
#(change requires
restart)
#shared_preload_libraries = '' # (change requires
restart)
# - Cost-Based Vacuum Delay -
#vacuum_cost_delay =
0ms # 0-100 milliseconds
#vacuum_cost_page_hit = 1 #
0-10000credits
#vacuum_cost_page_miss = 10 # 0-10000
credits
#vacuum_cost_page_dirty = 20 # 0-10000
credits
#vacuum_cost_limit =
200 # 1-10000 credits
# - Background Writer -
#bgwriter_delay =
200ms # 10-10000ms
between
rounds
#bgwriter_lru_maxpages = 100 # 0-1000 max
buffers
written/round
#bgwriter_lru_multiplier = 2.0 # 0-10.0 multipler on
buffers scanned/round
# - Asynchronous Behavior -
#effective_io_concurrency = 1 # 1-1000. 0 disables
prefetching
#------------------------------------------------------------------------------
# WRITE AHEAD LOG
#------------------------------------------------------------------------------
# - Settings -
#fsync =
on
#turns forced
synchronization on or off
#synchronous_commit =
on # immediate fsync at
commit
#wal_sync_method =
fsync # the default is the
first option
#supported by the
operating system:
# open_datasync
# fdatasync
# fsync
# fsync_writethrough
# open_sync
#full_page_writes =
on # recover from
partial
page writes
wal_buffers =
8MB
#min 32kB
#(change requires
restart)
#wal_writer_delay = 200ms #
1-10000milliseconds
#commit_delay =
0
#range 0-100000, in
microseconds
#commit_siblings =
5 #
range1-1000
# - Checkpoints -
checkpoint_segments =
32 # in logfile segments,
min 1, 16MB each
#checkpoint_timeout = 5min #
range30s-1h
#checkpoint_completion_target = 0.5 # checkpoint target
duration, 0.0 - 1.0
#checkpoint_warning = 30s #
0disables
# - Archiving -
#archive_mode = off # allows archiving
tobe done
#(change requires restart)
#archive_command = '' # command to use to archive a
logfile segment
#archive_timeout = 0 # force a logfile
segmentswitch
after this
#number of seconds; 0 disables
#------------------------------------------------------------------------------
# QUERY TUNING
#------------------------------------------------------------------------------
# - Planner Method Configuration -
#enable_bitmapscan = on
#enable_hashagg = on
#enable_hashjoin = on
#enable_indexscan = on
#enable_mergejoin = on
#enable_nestloop = on
#enable_seqscan = on
#enable_sort = on
#enable_tidscan = on
# - Planner Cost Constants -
#seq_page_cost =
1.0 #
measuredon an
arbitrary scale
random_page_cost =
3.0 # same scale
asabove
#cpu_tuple_cost =
0.01 # same scale
asabove
#cpu_index_tuple_cost = 0.005 # same scale as above
#cpu_operator_cost = 0.0025 # same
scaleas above
effective_cache_size = 12288MB
# - Genetic Query Optimizer -
#geqo = on
#geqo_threshold = 12
#geqo_effort =
5
#range 1-10
#geqo_pool_size =
0
#selects default based
on effort
#geqo_generations =
0 # selects
defaultbased
on effort
#geqo_selection_bias = 2.0 #
range1.5-2.0
# - Other Planner Options -
default_statistics_target = 100 # range 1-10000
#constraint_exclusion = partition # on, off, or partition
#cursor_tuple_fraction = 0.1 # range 0.0-1.0
#from_collapse_limit = 8
#join_collapse_limit =
8 # 1 disables collapsing
of explicit
#JOIN clauses
Hello if table is large, then client can raise this exception too try to set FETCH_COUNT to 1000 http://www.postgresql.org/docs/8.4/interactive/app-psql.html Regards Pavel Stehule 2011/8/30 Don <Donald.Laurine@noaa.gov>: > I am trying a simple access of a table and get an out of memory error. How > do I avoid this issue. It seems I have some configuration set wrong. > > Our system has 24GB of memory and is dedicated to the postgres database. > > Back ground information > > aquarec=> explain analyze verbose select * from ens_memb; > QUERY > PLAN > -------------------------------------------------------------------------------------------------------------------------- > Seq Scan on ens_memb (cost=0.00..719893.12 rows=32216212 width=62) (actual > time=4.954..37513.377 rows=32216154 loops=1) > Output: id, shefpc, bwmon, ewmon, pb, tb, cdate, vdate, source, tyr, val > Total runtime: 39588.386 ms > > > #------------------------------------------------------------------------------ > # RESOURCE USAGE (except WAL) > #------------------------------------------------------------------------------ > > # - Memory - > > shared_buffers = 6144MB # min 128kB > # (change requires restart) > #temp_buffers = 8MB # min 800kB > max_prepared_transactions = 5 # zero disables the feature > # (change requires restart) > # Note: Increasing max_prepared_transactions costs ~600 bytes of shared > memory > # per transaction slot, plus lock space (see max_locks_per_transaction). > # It is not advisable to set max_prepared_transactions nonzero unless you > # actively intend to use prepared transactions. > work_mem = 48MB # min 64kB > maintenance_work_mem = 256MB # min 1MB > #max_stack_depth = 2MB # min 100kB > > # - Kernel Resource Usage - > > #max_files_per_process = 1000 # min 25 > # (change requires restart) > #shared_preload_libraries = '' # (change requires restart) > > # - Cost-Based Vacuum Delay - > > #vacuum_cost_delay = 0ms # 0-100 milliseconds > #vacuum_cost_page_hit = 1 # 0-10000 credits > #vacuum_cost_page_miss = 10 # 0-10000 credits > #vacuum_cost_page_dirty = 20 # 0-10000 credits > #vacuum_cost_limit = 200 # 1-10000 credits > > # - Background Writer - > > #bgwriter_delay = 200ms # 10-10000ms between rounds > #bgwriter_lru_maxpages = 100 # 0-1000 max buffers written/round > #bgwriter_lru_multiplier = 2.0 # 0-10.0 multipler on buffers > scanned/round > > # - Asynchronous Behavior - > > #effective_io_concurrency = 1 # 1-1000. 0 disables prefetching > > > #------------------------------------------------------------------------------ > # WRITE AHEAD LOG > #------------------------------------------------------------------------------ > > # - Settings - > > #fsync = on # turns forced synchronization on or > off > #synchronous_commit = on # immediate fsync at commit > #wal_sync_method = fsync # the default is the first option > # supported by the operating system: > # open_datasync > # fdatasync > # fsync > # fsync_writethrough > # open_sync > #full_page_writes = on # recover from partial page writes > wal_buffers = 8MB # min 32kB > # (change requires restart) > #wal_writer_delay = 200ms # 1-10000 milliseconds > > #commit_delay = 0 # range 0-100000, in microseconds > #commit_siblings = 5 # range 1-1000 > > # - Checkpoints - > > checkpoint_segments = 32 # in logfile segments, min 1, 16MB > each > #checkpoint_timeout = 5min # range 30s-1h > #checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 - > 1.0 > #checkpoint_warning = 30s # 0 disables > > # - Archiving - > > #archive_mode = off # allows archiving to be done > # (change requires restart) > #archive_command = '' # command to use to archive a logfile > segment > #archive_timeout = 0 # force a logfile segment switch after this > # number of seconds; 0 disables > > #------------------------------------------------------------------------------ > # QUERY TUNING > #------------------------------------------------------------------------------ > > # - Planner Method Configuration - > > #enable_bitmapscan = on > #enable_hashagg = on > #enable_hashjoin = on > #enable_indexscan = on > #enable_mergejoin = on > #enable_nestloop = on > #enable_seqscan = on > #enable_sort = on > #enable_tidscan = on > > # - Planner Cost Constants - > > #seq_page_cost = 1.0 # measured on an arbitrary scale > random_page_cost = 3.0 # same scale as above > #cpu_tuple_cost = 0.01 # same scale as above > #cpu_index_tuple_cost = 0.005 # same scale as above > #cpu_operator_cost = 0.0025 # same scale as above > effective_cache_size = 12288MB > > # - Genetic Query Optimizer - > > #geqo = on > #geqo_threshold = 12 > #geqo_effort = 5 # range 1-10 > #geqo_pool_size = 0 # selects default based on effort > #geqo_generations = 0 # selects default based on effort > #geqo_selection_bias = 2.0 # range 1.5-2.0 > > # - Other Planner Options - > > default_statistics_target = 100 # range 1-10000 > #constraint_exclusion = partition # on, off, or partition > #cursor_tuple_fraction = 0.1 # range 0.0-1.0 > #from_collapse_limit = 8 > #join_collapse_limit = 8 # 1 disables collapsing of explicit > # JOIN clauses >
On 08/30/11 7:28 AM, Don wrote:
> I am trying a simple access of a table and get an out of memory
> error. How do I avoid this issue. It seems I have some configuration
> set wrong.
>
> Our system has 24GB of memory and is dedicated to the postgres database.
>
> Back ground information
>
> aquarec=> explain analyze verbose select * from ens_memb;
> QUERY PLAN
>
--------------------------------------------------------------------------------------------------------------------------
> Seq Scan on ens_memb (cost=0.00..719893.12 rows=32216212 width=62)
> (actual time=4.954..37513.377 rows=32216154 loops=1)
> Output: id, shefpc, bwmon, ewmon, pb, tb, cdate, vdate, source,
> tyr, val
> Total runtime: 39588.386 ms
wild guess (since you didn't show the error), your system doesn't have
enough memory available to store all 32 million rows of your result
set. This could be happening on the CLIENT ('psql') side or the server
side (and in fact, if both are on the same system, I believe that query
as written will require two copies of the result set in memory)
--
john r pierce N 37, W 122
santa cruz ca mid-left coast
Pavel... Thanks for the reply... This still did not solve the issue. It seems odd that a simple select command in psql accessing 32MB of records should cause a problem. I have tables much larger than this and may want to access them the same way. I have 24 GB RAM on the sever and 32GB RAM on the client machine. Both machines are 64bit. Thanks Don On 8/30/2011 10:25 AM, Pavel Stehule wrote: > Hello > > if table is large, then client can raise this exception too > > try to set FETCH_COUNT to 1000 > > http://www.postgresql.org/docs/8.4/interactive/app-psql.html > > Regards > > Pavel Stehule > > 2011/8/30 Don<Donald.Laurine@noaa.gov>: >> I am trying a simple access of a table and get an out of memory error. How >> do I avoid this issue. It seems I have some configuration set wrong. >> >> Our system has 24GB of memory and is dedicated to the postgres database. >> >> Back ground information >> >> aquarec=> explain analyze verbose select * from ens_memb; >> QUERY >> PLAN >> -------------------------------------------------------------------------------------------------------------------------- >> Seq Scan on ens_memb (cost=0.00..719893.12 rows=32216212 width=62) (actual >> time=4.954..37513.377 rows=32216154 loops=1) >> Output: id, shefpc, bwmon, ewmon, pb, tb, cdate, vdate, source, tyr, val >> Total runtime: 39588.386 ms >> >> >> #------------------------------------------------------------------------------ >> # RESOURCE USAGE (except WAL) >> #------------------------------------------------------------------------------ >> >> # - Memory - >> >> shared_buffers = 6144MB # min 128kB >> # (change requires restart) >> #temp_buffers = 8MB # min 800kB >> max_prepared_transactions = 5 # zero disables the feature >> # (change requires restart) >> # Note: Increasing max_prepared_transactions costs ~600 bytes of shared >> memory >> # per transaction slot, plus lock space (see max_locks_per_transaction). >> # It is not advisable to set max_prepared_transactions nonzero unless you >> # actively intend to use prepared transactions. >> work_mem = 48MB # min 64kB >> maintenance_work_mem = 256MB # min 1MB >> #max_stack_depth = 2MB # min 100kB >> >> # - Kernel Resource Usage - >> >> #max_files_per_process = 1000 # min 25 >> # (change requires restart) >> #shared_preload_libraries = '' # (change requires restart) >> >> # - Cost-Based Vacuum Delay - >> >> #vacuum_cost_delay = 0ms # 0-100 milliseconds >> #vacuum_cost_page_hit = 1 # 0-10000 credits >> #vacuum_cost_page_miss = 10 # 0-10000 credits >> #vacuum_cost_page_dirty = 20 # 0-10000 credits >> #vacuum_cost_limit = 200 # 1-10000 credits >> >> # - Background Writer - >> >> #bgwriter_delay = 200ms # 10-10000ms between rounds >> #bgwriter_lru_maxpages = 100 # 0-1000 max buffers written/round >> #bgwriter_lru_multiplier = 2.0 # 0-10.0 multipler on buffers >> scanned/round >> >> # - Asynchronous Behavior - >> >> #effective_io_concurrency = 1 # 1-1000. 0 disables prefetching >> >> >> #------------------------------------------------------------------------------ >> # WRITE AHEAD LOG >> #------------------------------------------------------------------------------ >> >> # - Settings - >> >> #fsync = on # turns forced synchronization on or >> off >> #synchronous_commit = on # immediate fsync at commit >> #wal_sync_method = fsync # the default is the first option >> # supported by the operating system: >> # open_datasync >> # fdatasync >> # fsync >> # fsync_writethrough >> # open_sync >> #full_page_writes = on # recover from partial page writes >> wal_buffers = 8MB # min 32kB >> # (change requires restart) >> #wal_writer_delay = 200ms # 1-10000 milliseconds >> >> #commit_delay = 0 # range 0-100000, in microseconds >> #commit_siblings = 5 # range 1-1000 >> >> # - Checkpoints - >> >> checkpoint_segments = 32 # in logfile segments, min 1, 16MB >> each >> #checkpoint_timeout = 5min # range 30s-1h >> #checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 - >> 1.0 >> #checkpoint_warning = 30s # 0 disables >> >> # - Archiving - >> >> #archive_mode = off # allows archiving to be done >> # (change requires restart) >> #archive_command = '' # command to use to archive a logfile >> segment >> #archive_timeout = 0 # force a logfile segment switch after this >> # number of seconds; 0 disables >> >> #------------------------------------------------------------------------------ >> # QUERY TUNING >> #------------------------------------------------------------------------------ >> >> # - Planner Method Configuration - >> >> #enable_bitmapscan = on >> #enable_hashagg = on >> #enable_hashjoin = on >> #enable_indexscan = on >> #enable_mergejoin = on >> #enable_nestloop = on >> #enable_seqscan = on >> #enable_sort = on >> #enable_tidscan = on >> >> # - Planner Cost Constants - >> >> #seq_page_cost = 1.0 # measured on an arbitrary scale >> random_page_cost = 3.0 # same scale as above >> #cpu_tuple_cost = 0.01 # same scale as above >> #cpu_index_tuple_cost = 0.005 # same scale as above >> #cpu_operator_cost = 0.0025 # same scale as above >> effective_cache_size = 12288MB >> >> # - Genetic Query Optimizer - >> >> #geqo = on >> #geqo_threshold = 12 >> #geqo_effort = 5 # range 1-10 >> #geqo_pool_size = 0 # selects default based on effort >> #geqo_generations = 0 # selects default based on effort >> #geqo_selection_bias = 2.0 # range 1.5-2.0 >> >> # - Other Planner Options - >> >> default_statistics_target = 100 # range 1-10000 >> #constraint_exclusion = partition # on, off, or partition >> #cursor_tuple_fraction = 0.1 # range 0.0-1.0 >> #from_collapse_limit = 8 >> #join_collapse_limit = 8 # 1 disables collapsing of explicit >> # JOIN clauses >>
On Aug 31, 2011, at 9:51 AM, Don wrote: > Both machines are 64bit. Are all your server & client builds 64-bit? 32M rows, unless the rows are <50 bytes each, you'll never be able to manipulate that selection in memory with a 32-bit app. -- Scott Ribe scott_ribe@elevated-dev.com http://www.elevated-dev.com/ (303) 722-0567 voice
Hello 2011/8/31 Don <Donald.Laurine@noaa.gov>: > Pavel... > > Thanks for the reply... > > This still did not solve the issue. It seems odd that a simple select > command in psql accessing 32MB of records should cause a problem. I have > tables much larger than this and may want to access them the same way. > so there are two possibilities a) broken datafiles b) PostgreSQL's bug Pavel > I have 24 GB RAM on the sever and 32GB RAM on the client machine. Both > machines are 64bit. > > Thanks Don > > > On 8/30/2011 10:25 AM, Pavel Stehule wrote: >> >> Hello >> >> if table is large, then client can raise this exception too >> >> try to set FETCH_COUNT to 1000 >> >> http://www.postgresql.org/docs/8.4/interactive/app-psql.html >> >> Regards >> >> Pavel Stehule >> >> 2011/8/30 Don<Donald.Laurine@noaa.gov>: >>> >>> I am trying a simple access of a table and get an out of memory error. >>> How >>> do I avoid this issue. It seems I have some configuration set wrong. >>> >>> Our system has 24GB of memory and is dedicated to the postgres database. >>> >>> Back ground information >>> >>> aquarec=> explain analyze verbose select * from ens_memb; >>> QUERY >>> PLAN >>> >>> -------------------------------------------------------------------------------------------------------------------------- >>> Seq Scan on ens_memb (cost=0.00..719893.12 rows=32216212 width=62) >>> (actual >>> time=4.954..37513.377 rows=32216154 loops=1) >>> Output: id, shefpc, bwmon, ewmon, pb, tb, cdate, vdate, source, tyr, >>> val >>> Total runtime: 39588.386 ms >>> >>> >>> >>> #------------------------------------------------------------------------------ >>> # RESOURCE USAGE (except WAL) >>> >>> #------------------------------------------------------------------------------ >>> >>> # - Memory - >>> >>> shared_buffers = 6144MB # min 128kB >>> # (change requires restart) >>> #temp_buffers = 8MB # min 800kB >>> max_prepared_transactions = 5 # zero disables the feature >>> # (change requires restart) >>> # Note: Increasing max_prepared_transactions costs ~600 bytes of shared >>> memory >>> # per transaction slot, plus lock space (see max_locks_per_transaction). >>> # It is not advisable to set max_prepared_transactions nonzero unless you >>> # actively intend to use prepared transactions. >>> work_mem = 48MB # min 64kB >>> maintenance_work_mem = 256MB # min 1MB >>> #max_stack_depth = 2MB # min 100kB >>> >>> # - Kernel Resource Usage - >>> >>> #max_files_per_process = 1000 # min 25 >>> # (change requires restart) >>> #shared_preload_libraries = '' # (change requires restart) >>> >>> # - Cost-Based Vacuum Delay - >>> >>> #vacuum_cost_delay = 0ms # 0-100 milliseconds >>> #vacuum_cost_page_hit = 1 # 0-10000 credits >>> #vacuum_cost_page_miss = 10 # 0-10000 credits >>> #vacuum_cost_page_dirty = 20 # 0-10000 credits >>> #vacuum_cost_limit = 200 # 1-10000 credits >>> >>> # - Background Writer - >>> >>> #bgwriter_delay = 200ms # 10-10000ms between rounds >>> #bgwriter_lru_maxpages = 100 # 0-1000 max buffers >>> written/round >>> #bgwriter_lru_multiplier = 2.0 # 0-10.0 multipler on buffers >>> scanned/round >>> >>> # - Asynchronous Behavior - >>> >>> #effective_io_concurrency = 1 # 1-1000. 0 disables prefetching >>> >>> >>> >>> #------------------------------------------------------------------------------ >>> # WRITE AHEAD LOG >>> >>> #------------------------------------------------------------------------------ >>> >>> # - Settings - >>> >>> #fsync = on # turns forced synchronization on >>> or >>> off >>> #synchronous_commit = on # immediate fsync at commit >>> #wal_sync_method = fsync # the default is the first option >>> # supported by the operating >>> system: >>> # open_datasync >>> # fdatasync >>> # fsync >>> # fsync_writethrough >>> # open_sync >>> #full_page_writes = on # recover from partial page >>> writes >>> wal_buffers = 8MB # min 32kB >>> # (change requires restart) >>> #wal_writer_delay = 200ms # 1-10000 milliseconds >>> >>> #commit_delay = 0 # range 0-100000, in microseconds >>> #commit_siblings = 5 # range 1-1000 >>> >>> # - Checkpoints - >>> >>> checkpoint_segments = 32 # in logfile segments, min 1, >>> 16MB >>> each >>> #checkpoint_timeout = 5min # range 30s-1h >>> #checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 >>> - >>> 1.0 >>> #checkpoint_warning = 30s # 0 disables >>> >>> # - Archiving - >>> >>> #archive_mode = off # allows archiving to be done >>> # (change requires restart) >>> #archive_command = '' # command to use to archive a logfile >>> segment >>> #archive_timeout = 0 # force a logfile segment switch after >>> this >>> # number of seconds; 0 disables >>> >>> >>> #------------------------------------------------------------------------------ >>> # QUERY TUNING >>> >>> #------------------------------------------------------------------------------ >>> >>> # - Planner Method Configuration - >>> >>> #enable_bitmapscan = on >>> #enable_hashagg = on >>> #enable_hashjoin = on >>> #enable_indexscan = on >>> #enable_mergejoin = on >>> #enable_nestloop = on >>> #enable_seqscan = on >>> #enable_sort = on >>> #enable_tidscan = on >>> >>> # - Planner Cost Constants - >>> >>> #seq_page_cost = 1.0 # measured on an arbitrary scale >>> random_page_cost = 3.0 # same scale as above >>> #cpu_tuple_cost = 0.01 # same scale as above >>> #cpu_index_tuple_cost = 0.005 # same scale as above >>> #cpu_operator_cost = 0.0025 # same scale as above >>> effective_cache_size = 12288MB >>> >>> # - Genetic Query Optimizer - >>> >>> #geqo = on >>> #geqo_threshold = 12 >>> #geqo_effort = 5 # range 1-10 >>> #geqo_pool_size = 0 # selects default based on effort >>> #geqo_generations = 0 # selects default based on effort >>> #geqo_selection_bias = 2.0 # range 1.5-2.0 >>> >>> # - Other Planner Options - >>> >>> default_statistics_target = 100 # range 1-10000 >>> #constraint_exclusion = partition # on, off, or partition >>> #cursor_tuple_fraction = 0.1 # range 0.0-1.0 >>> #from_collapse_limit = 8 >>> #join_collapse_limit = 8 # 1 disables collapsing of >>> explicit >>> # JOIN clauses >>> > >
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The server is 64 bit and client is 32 bit... I tried the select
* from table on the server and the query worked...
but I am puzzled why it does not work on the 32bit machine. I had
always thought that a 32bit machine could access up to 4GB.
So what is the limiting factor ?
On 8/31/2011 8:57 AM, Scott Ribe wrote:
<blockquote
cite="mid:AD443F0B-D050-4E79-B277-AF9A5DB9AF06@elevated-dev.com"
type="cite">
On Aug 31, 2011, at 9:51 AM, Don wrote:
Both machines are 64bit.
Are all your server & client builds 64-bit?
32M rows, unless the rows are <50 bytes each, you'll never be able to manipulate that selection in memory with a
32-bitapp.
On Aug 31, 2011, at 10:52 AM, Don wrote: > I had always thought that a 32bit machine could access up to 4GB. > So what is the limiting factor ? - Half of your memory space may be given over to memory-mapped I/O. Now you're down to 2GB. - Your process's executable, plus any libraries it uses, plus all the system libraries that they touch, recursively all theway down, are mapped into this space. Now you're likely down to 1.5GB or less free. - Then of course your process allocates various data structures for each row, even if it's just a huge array of pointersto each row, that would be overhead. And of course the overhead is not nearly that simple--there will be allocationsfor & pointers to varchars, and info about columns and data types, and heap data structures to keep track of allocatedvs free blocks. - Memory will be fragmented of course, so you can't even use all of what's left. So no, you can't manipulate 32M of anything except plain numbers or very simple structs in RAM in a 32-bit process. -- Scott Ribe scott_ribe@elevated-dev.com http://www.elevated-dev.com/ (303) 722-0567 voice