valkey/tests/integration/psync2-pingoff.tcl
naglera 28e055af0b
Deflake chained replicas disconnect (#574)
Deflake chained replicas disconnect when replica re-connect with the
same master. sync_partial_ok counter might get incremented if replica
timed out during test.

Signed-off-by: naglera <anagler123@gmail.com>
2024-06-02 20:53:39 -07:00

252 lines
9.5 KiB
Tcl

# These tests were added together with the meaningful offset implementation
# in valkey OSS 6.0.0, which was later abandoned in 6.0.4, they used to test that
# servers are able to PSYNC with replicas even if the replication stream has
# PINGs at the end which present in one sever and missing on another.
# We keep these tests just because they reproduce edge cases in the replication
# logic in hope they'll be able to spot some problem in the future.
start_server {tags {"psync2 external:skip"}} {
start_server {} {
# Config
set debug_msg 0 ; # Enable additional debug messages
for {set j 0} {$j < 2} {incr j} {
set R($j) [srv [expr 0-$j] client]
set R_host($j) [srv [expr 0-$j] host]
set R_port($j) [srv [expr 0-$j] port]
$R($j) CONFIG SET repl-ping-replica-period 1
if {$debug_msg} {puts "Log file: [srv [expr 0-$j] stdout]"}
}
# Setup replication
test "PSYNC2 pingoff: setup" {
$R(1) replicaof $R_host(0) $R_port(0)
$R(0) set foo bar
wait_for_condition 50 1000 {
[status $R(1) master_link_status] == "up" &&
[$R(0) dbsize] == 1 && [$R(1) dbsize] == 1
} else {
fail "Replicas not replicating from master"
}
}
test "PSYNC2 pingoff: write and wait replication" {
$R(0) INCR counter
$R(0) INCR counter
$R(0) INCR counter
wait_for_condition 50 1000 {
[$R(0) GET counter] eq [$R(1) GET counter]
} else {
fail "Master and replica don't agree about counter"
}
}
# In this test we'll make sure the replica will get stuck, but with
# an active connection: this way the master will continue to send PINGs
# every second (we modified the PING period earlier)
test "PSYNC2 pingoff: pause replica and promote it" {
$R(1) MULTI
$R(1) DEBUG SLEEP 5
$R(1) SLAVEOF NO ONE
$R(1) EXEC
$R(1) ping ; # Wait for it to return back available
}
test "Make the old master a replica of the new one and check conditions" {
# We set the new master's ping period to a high value, so that there's
# no chance for a race condition of sending a PING in between the two
# INFO calls in the assert for master_repl_offset match below.
$R(1) CONFIG SET repl-ping-replica-period 1000
assert_equal [status $R(1) sync_full] 0
$R(0) REPLICAOF $R_host(1) $R_port(1)
wait_for_condition 50 1000 {
[status $R(0) master_link_status] == "up"
} else {
fail "The new master was not able to sync"
}
# make sure replication is still alive and kicking
$R(1) incr x
wait_for_condition 50 1000 {
[status $R(0) loading] == 0 &&
[$R(0) get x] == 1
} else {
fail "replica didn't get incr"
}
assert_equal [status $R(0) master_repl_offset] [status $R(1) master_repl_offset]
}
}}
start_server {tags {"psync2 external:skip"}} {
start_server {} {
start_server {} {
start_server {} {
start_server {} {
test {test various edge cases of repl topology changes with missing pings at the end} {
set master [srv -4 client]
set master_host [srv -4 host]
set master_port [srv -4 port]
set replica1 [srv -3 client]
set replica2 [srv -2 client]
set replica3 [srv -1 client]
set replica4 [srv -0 client]
$replica1 replicaof $master_host $master_port
$replica2 replicaof $master_host $master_port
$replica3 replicaof $master_host $master_port
$replica4 replicaof $master_host $master_port
wait_for_condition 50 1000 {
[status $master connected_slaves] == 4
} else {
fail "replicas didn't connect"
}
$master incr x
wait_for_condition 50 1000 {
[$replica1 get x] == 1 && [$replica2 get x] == 1 &&
[$replica3 get x] == 1 && [$replica4 get x] == 1
} else {
fail "replicas didn't get incr"
}
# disconnect replica1 and replica2
# and wait for the master to send a ping to replica3 and replica4
$replica1 replicaof no one
$replica2 replicaof 127.0.0.1 1 ;# we can't promote it to master since that will cycle the replication id
$master config set repl-ping-replica-period 1
set replofs [status $master master_repl_offset]
wait_for_condition 50 100 {
[status $replica3 master_repl_offset] > $replofs &&
[status $replica4 master_repl_offset] > $replofs
} else {
fail "replica didn't sync in time"
}
# make everyone sync from the replica1 that didn't get the last ping from the old master
# replica4 will keep syncing from the old master which now syncs from replica1
# and replica2 will re-connect to the old master (which went back in time)
set new_master_host [srv -3 host]
set new_master_port [srv -3 port]
$replica3 replicaof $new_master_host $new_master_port
$master replicaof $new_master_host $new_master_port
$replica2 replicaof $master_host $master_port
wait_for_condition 50 1000 {
[status $replica2 master_link_status] == "up" &&
[status $replica3 master_link_status] == "up" &&
[status $replica4 master_link_status] == "up" &&
[status $master master_link_status] == "up"
} else {
fail "replicas didn't connect"
}
# make sure replication is still alive and kicking
$replica1 incr x
wait_for_condition 50 1000 {
[$replica2 get x] == 2 &&
[$replica3 get x] == 2 &&
[$replica4 get x] == 2 &&
[$master get x] == 2
} else {
fail "replicas didn't get incr"
}
# make sure we have the right amount of full syncs
assert_equal [status $master sync_full] 6
assert_equal [status $replica1 sync_full] 2
assert_equal [status $replica2 sync_full] 0
assert_equal [status $replica3 sync_full] 0
assert_equal [status $replica4 sync_full] 0
# force psync
$master client kill type master
$replica2 client kill type master
$replica3 client kill type master
$replica4 client kill type master
# make sure replication is still alive and kicking
$replica1 incr x
wait_for_condition 50 1000 {
[$replica2 get x] == 3 &&
[$replica3 get x] == 3 &&
[$replica4 get x] == 3 &&
[$master get x] == 3
} else {
fail "replicas didn't get incr"
}
# make sure we have the right amount of full syncs
assert_equal [status $master sync_full] 6
assert_equal [status $replica1 sync_full] 2
assert_equal [status $replica2 sync_full] 0
assert_equal [status $replica3 sync_full] 0
assert_equal [status $replica4 sync_full] 0
}
}}}}}
start_server {tags {"psync2 external:skip"}} {
start_server {} {
start_server {} {
for {set j 0} {$j < 3} {incr j} {
set R($j) [srv [expr 0-$j] client]
set R_host($j) [srv [expr 0-$j] host]
set R_port($j) [srv [expr 0-$j] port]
$R($j) CONFIG SET repl-ping-replica-period 1
$R($j) config set repl-timeout 300
}
test "Chained replicas disconnect when replica re-connect with the same master" {
# Add a second replica as a chained replica of the current replica
$R(1) replicaof $R_host(0) $R_port(0)
$R(2) replicaof $R_host(1) $R_port(1)
wait_for_condition 50 1000 {
[status $R(2) master_link_status] == "up"
} else {
fail "Chained replica not replicating from its master"
}
# Do a write on the master, and wait for the master to
# send some PINGs to its replica
$R(0) INCR counter2
set replofs [status $R(0) master_repl_offset]
wait_for_condition 50 100 {
[status $R(1) master_repl_offset] > $replofs &&
[status $R(2) master_repl_offset] > $replofs
} else {
fail "replica didn't sync in time"
}
set sync_partial_master [status $R(0) sync_partial_ok]
set sync_partial_replica [status $R(1) sync_partial_ok]
$R(0) CONFIG SET repl-ping-replica-period 100
# Disconnect the master's direct replica
$R(0) client kill type replica
wait_for_condition 50 1000 {
[status $R(1) master_link_status] == "up" &&
[status $R(2) master_link_status] == "up" &&
[status $R(0) sync_partial_ok] == $sync_partial_master + 1 &&
[status $R(1) sync_partial_ok] == $sync_partial_replica
} else {
fail "Disconnected replica failed to PSYNC with master"
}
# Verify that the replica and its replica's meaningful and real
# offsets match with the master
assert_equal [status $R(0) master_repl_offset] [status $R(1) master_repl_offset]
assert_equal [status $R(0) master_repl_offset] [status $R(2) master_repl_offset]
# make sure replication is still alive and kicking
$R(0) incr counter2
wait_for_condition 50 1000 {
[$R(1) get counter2] == 2 && [$R(2) get counter2] == 2
} else {
fail "replicas didn't get incr"
}
assert_equal [status $R(0) master_repl_offset] [status $R(1) master_repl_offset]
assert_equal [status $R(0) master_repl_offset] [status $R(2) master_repl_offset]
}
}}}