could not fork new process for connection: Resource temporarily unavailable

ello,

I have heavy transaction load production database 9.3 PPAS .Today Database
is not able to give new process. I checked pg_stat_activity , there are so
many transaction in waiting stage because of one procedure and lock on one
table (Code inside procedure)

SELECT cnt
FROM table_name_seq_data
WHERE circle = v_cir_cd
AND type = P_NAME FOR UPDATE;

I have terminated all transaction related to that procedure , but again
locks occurred and no new process allowed.3 times I have performed this
thing. After that I have restated my server, then I executed this procedure
it takes very less ms. I have to take lock of this table
(table_name_seq_data).

Log files

could not fork new process for connection: Resource temporarily
unavailable
could not fork new process for connection: Resource temporarily
unavailable
could not fork autovacuum worker process: Resource temporarily unavailable
could not fork new process for connection: Resource temporarily
unavailable
could not fork new process for connection: Resource temporarily
unavailable

I think because of Application workload this table(table_name_seq_data) is
not vacuumed . This table contains only 50 rows only updates occur on this
table, And before restart I am not able select this table.

------------------------------------------------------------------------------------------
# - Cost-Based Vacuum Delay -

#vacuum_cost_delay = 0 # 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 = 1000 # 1-10000 credits

#vacuum_defer_cleanup_age = 0 # number of xacts by which cleanup is delayed

#------------------------------------------------------------------------------
# AUTOVACUUM PARAMETERS
#------------------------------------------------------------------------------

autovacuum = on # Enable autovacuum subprocess? 'on'
# requires track_counts to also be on.
#log_autovacuum_min_duration = -1 # -1 disables, 0 logs all actions and
# their durations, > 0 logs only
# actions running at least this number
# of milliseconds.
autovacuum_max_workers = 6 # max number of autovacuum subprocesses
# (change requires restart)
#autovacuum_naptime = 1min # time between autovacuum runs
autovacuum_vacuum_threshold = 2000 # min number of row updates before
# vacuum
autovacuum_analyze_threshold = 2000 # min number of row updates before
# analyze
#autovacuum_vacuum_scale_factor = 0.2 # fraction of table size before vacuum
#autovacuum_analyze_scale_factor = 0.1 # fraction of table size before
analyze
#autovacuum_freeze_max_age = 200000000 # maximum XID age before forced
vacuum
# (change requires restart)
#autovacuum_vacuum_cost_delay = 20ms # default vacuum cost delay for
# autovacuum, in milliseconds;
# -1 means use vacuum_cost_delay
#autovacuum_vacuum_cost_limit = -1 # default vacuum cost limit for
# autovacuum, -1 means use
# vacuum_cost_limit