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From 26b15d4eb7ac71fcab28a7fca664afa0549c135c Mon Sep 17 00:00:00 2001
From: Thomas Sanders <thomas.sanders@citrix.com>
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 <thomas.sanders@citrix.com>
---
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
|
