From 41f706134365c43ab79dc0383965df267eece0e2 Mon Sep 17 00:00:00 2001 From: "Richard W.M. Jones" Date: Sat, 16 Feb 2008 16:29:02 +0000 Subject: Store domain %CPU and memory history. --- virt-ctrl/vc_connections.ml | 133 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 105 insertions(+), 28 deletions(-) diff --git a/virt-ctrl/vc_connections.ml b/virt-ctrl/vc_connections.ml index 7e58aee..210c68a 100644 --- a/virt-ctrl/vc_connections.ml +++ b/virt-ctrl/vc_connections.ml @@ -53,18 +53,45 @@ and connection = int (* connection ID *) * (active list * inactive list) and active = int (* domain's ID *) and inactive = string (* domain's name *) -(* The last "CPU time" seen for a domain, so we can calculate CPU % usage. - * Hash of (connid, domid) -> cpu_time [int64]. - *) -let last_cpu_time = Hashtbl.create 13 -let last_time = ref (Unix.gettimeofday ()) - (* Store the node_info and hostname for each connection, fetched * once just after we connect since these don't normally change. * Hash of connid -> (C.node_info, hostname option, uri) *) let static_conn_info = Hashtbl.create 13 +(* Stores the state and history for each domain. + * Hash of (connid, domid) -> mutable domhistory structure. + * We never delete entries in this hash table, which may be a problem + * for very very long-lived instances of virt-ctrl. + *) +type domhistory = { + (* for %CPU calculation: *) + mutable last_cpu_time : int64; (* last virDomainInfo->cpuTime *) + mutable last_time : float; (* exact time we measured the above *) + + (* historical data for graphs etc: *) + mutable hist_cpu : int array; (* historical %CPU *) + mutable hist_cpu_posn : int; (* position within array *) + mutable hist_mem : int64 array; (* historical memory (kilobytes) *) + mutable hist_mem_posn : int; (* position within array *) +} + +let domhistory = Hashtbl.create 13 + +let new_domhistory () = { + last_cpu_time = 0L; last_time = 0.; + hist_cpu = Array.make 0 0; hist_cpu_posn = 0; + hist_mem = Array.make 0 0L; hist_mem_posn = 0; +} + +(* These set limits on the amount of history we collect. *) +let hist_max = 86400 (* max history stored, seconds *) +let hist_rot = 3600 (* rotation of array when we hit max *) + +(* The types of the display columns in the main window. The interesting + * one of the final (int) field which stores the ID of the row, either + * connid or domid. + *) type columns = string GTree.column * string GTree.column * string GTree.column * string GTree.column * string GTree.column * int GTree.column let debug_repopulate = true @@ -75,12 +102,6 @@ let debug_repopulate = true let repopulate (tree : GTree.view) (model : GTree.tree_store) (col_name_id, col_domname, col_status, col_cpu, col_mem, col_id) state = - let time_passed = - let time_now = Unix.gettimeofday () in - let time_passed = time_now -. !last_time in - last_time := time_now; - time_passed in - (* Which connections have been added or removed? *) let conns = get_conns () in let added, _, removed = @@ -226,23 +247,79 @@ let repopulate (tree : GTree.view) (model : GTree.tree_store) let memory = sprintf "%Ld K" info.D.memory in model#set ~row ~column:col_mem memory; - let ns_now = info.D.cpu_time in (* ns = nanoseconds *) - let ns_prev = - try - let ns = Hashtbl.find last_cpu_time (conn_id, domid) in - if ns > ns_now then 0L else ns (* Rebooted? *) - with Not_found -> 0L in - Hashtbl.replace last_cpu_time (conn_id, domid) ns_now; - let ns_now = Int64.to_float ns_now in - let ns_prev = Int64.to_float ns_prev in - let ns_used = ns_now -. ns_prev in - let ns_available = 1_000_000_000. *. float nr_cpus in - let cpu_percent = - 100. *. (ns_used /. ns_available) /. time_passed in - let cpu_percent = sprintf "%.1f %%" cpu_percent in - model#set ~row ~column:col_cpu cpu_percent; + (* Get domhistory. For a new domain it won't exist, so + * create an empty one. + *) + let dh = + let key = conn_id, domid in + try Hashtbl.find domhistory key + with Not_found -> + let dh = new_domhistory () in + Hashtbl.add domhistory key dh; + dh in + + (* Measure current time and domain cpuTime as close + * together as possible. + *) + let time_now = Unix.gettimeofday () in + let cpu_now = info.D.cpu_time in + + let time_prev = dh.last_time in + let cpu_prev = + if dh.last_cpu_time > cpu_now then 0L (* Rebooted? *) + else dh.last_cpu_time in + + dh.last_time <- time_now; + dh.last_cpu_time <- cpu_now; - with Libvirt.Virterror _ -> () (* Ignore any transient error *) + let cpu_percent = + if time_prev > 0. then ( + let cpu_now = Int64.to_float cpu_now in + let cpu_prev = Int64.to_float cpu_prev in + let cpu_used = cpu_now -. cpu_prev in + let cpu_available = 1_000_000_000. *. float nr_cpus in + let time_passed = time_now -. time_prev in + + let cpu_percent = + 100. *. (cpu_used /. cpu_available) /. time_passed in + + let cpu_percent_str = sprintf "%.1f %%" cpu_percent in + model#set ~row ~column:col_cpu cpu_percent_str; + int_of_float cpu_percent + ) else -1 in + + (* Store history. *) + let store arr posn datum = + if posn >= hist_max then ( + (* rotate the array *) + Array.blit arr hist_rot arr 0 (hist_max - hist_rot); + let posn = posn - hist_rot in + arr.(posn) <- datum; + (arr, posn+1) + ) else ( + let len = Array.length arr in + if posn < len then ( + (* normal update *) + arr.(posn) <- datum; + (arr, posn+1) + ) else ( + (* extend the array *) + let len' = min (max (2*len) 1) hist_max in + let arr' = Array.make len' datum in + Array.blit arr 0 arr' 0 len; + (arr', posn+1) + ) + ) + in + let hist_cpu, hist_cpu_posn = + store dh.hist_cpu dh.hist_cpu_posn cpu_percent in + dh.hist_cpu <- hist_cpu; dh.hist_cpu_posn <- hist_cpu_posn; + let hist_mem, hist_mem_posn = + store dh.hist_mem dh.hist_mem_posn info.D.memory in + dh.hist_mem <- hist_mem; dh.hist_mem_posn <- hist_mem_posn + + with + Libvirt.Virterror _ -> () (* Ignore any transient error *) ) ) (model#iter_children (Some parent)); -- cgit