From 26b15d4eb7ac71fcab28a7fca664afa0549c135c Mon Sep 17 00:00:00 2001 From: Thomas Sanders Date: Tue, 28 Mar 2017 18:57:52 +0100 Subject: [PATCH 16/15] oxenstored: trim history in the frequent_ops function We were trimming the history of commits only at the end of each transaction (regardless of how it ended). Therefore if non-transactional writes were being made but no transactions were being ended, the history would grow indefinitely. Now we trim the history at regular intervals. Signed-off-by: Thomas Sanders --- tools/ocaml/xenstored/history.ml | 6 +++--- tools/ocaml/xenstored/transaction.ml | 8 ++++++-- tools/ocaml/xenstored/xenstored.ml | 1 + 3 files changed, 10 insertions(+), 5 deletions(-) diff --git a/tools/ocaml/xenstored/history.ml b/tools/ocaml/xenstored/history.ml index 4079588..f39565b 100644 --- a/tools/ocaml/xenstored/history.ml +++ b/tools/ocaml/xenstored/history.ml @@ -39,7 +39,8 @@ let mark_symbols () = (* Keep only enough commit-history to protect the running transactions that we are still tracking *) (* There is scope for optimisation here, replacing List.filter with something more efficient, * probably on a different list-like structure. *) -let trim () = +let trim ?txn () = + Transaction.trim_short_running_transactions txn; history := match Transaction.oldest_short_running_transaction () with | None -> [] (* We have no open transaction, so no history is needed *) | Some (_, txn) -> ( @@ -49,8 +50,7 @@ let trim () = let end_transaction txn con tid commit = let success = Connection.end_transaction con tid commit in - Transaction.end_transaction txn; - trim (); + trim ~txn (); success let push (x: history_record) = diff --git a/tools/ocaml/xenstored/transaction.ml b/tools/ocaml/xenstored/transaction.ml index da4a3e3..23e7ccf 100644 --- a/tools/ocaml/xenstored/transaction.ml +++ b/tools/ocaml/xenstored/transaction.ml @@ -106,10 +106,14 @@ let oldest_short_running_transaction () = | x :: xs -> last xs in last !short_running_txns -let end_transaction txn = +let trim_short_running_transactions txn = let cutoff = Unix.gettimeofday () -. !Define.conflict_max_history_seconds in + let keep = match txn with + | None -> (function (start_time, _) -> start_time >= cutoff) + | Some t -> (function (start_time, tx) -> start_time >= cutoff && tx != t) + in short_running_txns := List.filter - (function (start_time, tx) -> start_time >= cutoff && tx != txn) + keep !short_running_txns let make ?(internal=false) id store = diff --git a/tools/ocaml/xenstored/xenstored.ml b/tools/ocaml/xenstored/xenstored.ml index 92ea99e..c45146d 100644 --- a/tools/ocaml/xenstored/xenstored.ml +++ b/tools/ocaml/xenstored/xenstored.ml @@ -280,6 +280,7 @@ let _ = * than the periodic_ops function *) let frequent_ops () = if Unix.gettimeofday () > !next_frequent_ops then ( + History.trim (); Domains.incr_conflict_credit domains; advance_next_frequent_ops () ) in -- 1.7.9.5