test/format failed with stuck cache

format run exceeded 15 minutes past the maximum time, aborting the process

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#  RUN PARAMETERS

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abort=0

alter=0

auto_throttle=1

backups=0

bitcnt=4

bloom=1

bloom_bit_count=24

bloom_hash_count=15

bloom_oldest=0

cache=20

cache_minimum=20

checkpoints=on

checkpoint_log_size=142

checkpoint_wait=73

checksum=off

chunk_size=3

compaction=0

compression=lz4-noraw

data_extend=0

data_source=table

delete_pct=30

dictionary=0

direct_io=0

encryption=none

evict_max=1

file_type=variable-length column-store

firstfit=0

huffman_key=0

huffman_value=0

independent_thread_rng=0

in_memory=0

insert_pct=20

internal_key_truncation=1

internal_page_max=11

isolation=random

key_gap=15

key_max=31

key_min=21

leaf_page_max=16

leak_memory=0

logging=0

logging_archive=1

logging_compression=none

logging_file_max=188180

logging_prealloc=0

long_running_txn=0

lsm_worker_threads=3

merge_max=20

mmap=1

modify_pct=19

ops=0

prefix_compression=1

prefix_compression_min=2

prepare=0

quiet=1

read_pct=9

rebalance=1

repeat_data_pct=90

reverse=0

rows=1000000

runs=1

salvage=1

split_pct=76

statistics=0

statistics_server=0

threads=17

timer=4

timing_stress_checkpoint=0

timing_stress_lookaside_sweep=0

timing_stress_split_1=1

timing_stress_split_2=0

timing_stress_split_3=0

timing_stress_split_4=1

timing_stress_split_5=1

timing_stress_split_6=1

timing_stress_split_7=1

transaction_timestamps=0

transaction-frequency=70

truncate=1

value_max=1152

value_min=3

verify=1

wiredtiger_config=

write_pct=22

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