Currently there’s no queue features in Transmission. Luckily we can improvise this with the help of transmission-remote, a command based client for transmission, and along with some Linux bash scripting.

Below I have created a simple bash script:

1. Install transmission remote:
sudo apt-get install transmission-cli

2. Copy the script below, and save as my_script_name.sh , (or whatever name you prefer, but note the .sh extension).

#!/bin/sh
 
# *************
# Configuration
REMOTE="/usr/bin/transmission-remote"
USERNAME="my_username"
PASSWORD="my_password"
MAXDOWN="max_number_of_torrent_to_download"
MAXACTIVE="max_active_torrent"
CONFIG="/my_location_to_transmission_config_file/settings.json"
TRANSOPTS="127.0.0.1:my_port_number"
 
# *************
# Set-up variables
CMD="$REMOTE $TRANSOPTS --auth $USERNAME:$PASSWORD"
LOGCMD="/usr/bin/logger -t transmission-queue "
MAXRATIO=$(cat $CONFIG | grep \"ratio-limit\":)
MAXRATIO=${MAXRATIO#*\"ratio-limit\": }
MAXRATIO=${MAXRATIO%*, }
 
# *************
# deal with downloads
DOWNACTIVE="$($CMD -l | tail --lines=+2 | grep -v 100% | grep -v Sum | grep -v Stopped | grep -v Verifying | grep -v Will\ Verify | wc -l)"
if [ $MAXDOWN -lt $DOWNACTIVE ]; then
    DOWNTOSTOP="$($CMD -l | tail --lines=+2 | grep -v 100% | grep -v Sum | grep -v Stopped | grep -v Verifying | grep -v Will\ Verify | tail -n $(expr $DOWNACTIVE - $MAXDOWN) | awk '{ print $1; }')"
    for ID in $DOWNTOSTOP; do
        NAME="$($CMD --torrent $ID --info | grep Name:)"
        $LOGCMD "< << $ID: ${NAME#*Name: }"
        $CMD --torrent $ID --stop >> /dev/null 2>&1
    done
else
    [ $(expr $MAXDOWN - $DOWNACTIVE) -gt 0 ] && (
    DOWNINACTIVE="$($CMD -l | tail --lines=+2 | grep -v 100% | grep Stopped | wc -l)"
    [ $DOWNINACTIVE -gt 0 ] && (
        DOWNTOSTART="$($CMD -l | tail --lines=+2 | grep -v 100% | grep Stopped | head -n $(expr $MAXDOWN - $DOWNACTIVE) | awk '{ print $1; }')"
        for ID in $DOWNTOSTART; do
            NAME="$($CMD --torrent $ID --info | grep Name:)"
            $LOGCMD ">>> $ID: ${NAME#*Name: }"
            $CMD --torrent $ID --start >> /dev/null 2>&1
        done
        )
    )
fi
# Then deal with total active
ACTIVE="$($CMD -l | tail --lines=+2 | grep -v Sum | grep -v Stopped | grep -v Verifying | grep -v Will\ Verify | wc -l)"
if [ $MAXACTIVE -lt $ACTIVE ]; then
    TOSTOP="$($CMD -l | tail --lines=+2 | grep 100% | grep -v Stopped | grep -v Verifying | grep -v Will\ Verify | tail -n $(expr $ACTIVE - $MAXACTIVE) | awk '{ print $1; }')"
    for ID in $TOSTOP; do
        NAME="$($CMD --torrent $ID --info | grep Name:)"
        $LOGCMD "< << $ID: ${NAME#*Name: }"
        $CMD --torrent $ID --stop >> /dev/null 2>&1
    done
else
    [ $(expr $MAXACTIVE - $ACTIVE) -gt 0 ] && (
    SEEDINACTIVE="$($CMD -l | tail --lines=+2 | grep 100% | grep Stopped | awk -v ratio=$MAXRATIO '{ if (strtonum(substr($0,52,4)) < ratio) print $0 ;}' | wc -l)"
    [ $SEEDINACTIVE -gt 0 ] && (
        TOSTART="$($CMD -l | tail --lines=+2 | grep 100% | grep Stopped | awk -v ratio=$MAXRATIO '{ if (strtonum(substr($0,52,4)) < ratio) print $0 ;}' | head -n $(expr $MAXACTIVE - $ACTIVE) | awk '{ print $1; }')"
        for ID in $TOSTART; do
            NAME="$($CMD --torrent $ID --info | grep Name:)"
            $LOGCMD ">>> $ID: ${NAME#*Name: }"
            $CMD --torrent $ID --start >> /dev/null 2>&1
        done
        )
    )
fi

Save the script on any location you prefer.

3. Create a cron job to run the script. Open the entry to crontab:
crontab -e

4. Let say you want to run the script 5 minutes, the entry on your cron job should be as below:
*/5 * * * * sh /location_to_my_script/my_script_name.sh

Script courtesy of www.4geeksfromnet.com