The Jenkins job wiredtiger-test-format-stress-sanitizer failed because it detected page entries that should have been run-length encoded but weren't.
http://build.wiredtiger.com:8080/job/wiredtiger-test-format-stress-sanitizer/23804/
The error:
[1552549540:600801][8983:0x7fd9d64f9700], t, file:wt, WT_SESSION.commit_transaction: __verify_dsk_col_var, 805: data entries 10 and 11 on page at [reconcile-image] are identical and should have been run-length encoded [1552549577:68774][8983:0x7fd9dd8f9700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 16 and 17 on page at [reconcile-image] are identical and should have been run-length encoded [1552549581:85255][8983:0x7fd9dd8f9700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 4 and 5 on page at [reconcile-image] are identical and should have been run-length encoded [1552549603:391453][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 4 and 5 on page at [reconcile-image] are identical and should have been run-length encoded [1552549625:980855][8983:0x7fd9d67e5700], t, file:wt, WT_SESSION.rollback_transaction: __verify_dsk_col_var, 805: data entries 13 and 14 on page at [reconcile-image] are identical and should have been run-length encoded [1552549677:548771][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549677:643169][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549677:791150][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549677:879862][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549678:13229][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549678:280625][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549678:914396][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:150350][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:276639][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 8 and 9 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:276869][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 2 and 3 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:317599][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:394062][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:470675][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:534217][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 2 and 3 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:537678][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 8 and 9 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:835018][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549679:933374][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549680:23400][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 8 and 9 on page at [reconcile-image] are identical and should have been run-length encoded [1552549680:23949][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 2 and 3 on page at [reconcile-image] are identical and should have been run-length encoded [1552549680:145898][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 5 and 6 on page at [reconcile-image] are identical and should have been run-length encoded [1552549681:706070][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 6 and 7 on page at [write-check] are identical and should have been run-length encoded [1552549719:837356][8983:0x7fd9dd8f9700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549722:215801][8983:0x7fd9dd8f9700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded [1552549733:107350][8983:0x7fd9dd0f8700], t, file:wt, eviction-server: __verify_dsk_col_var, 805: data entries 3 and 4 on page at [reconcile-image] are identical and should have been run-length encoded t: process 8983