Date: Thu, 18 Dec 2014 08:46:54 +0000 (UTC) From: Alexander Motin <mav@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r275895 - in stable/10: sys/cam/ctl usr.sbin/ctladm Message-ID: <201412180846.sBI8ksW7030654@svn.freebsd.org>
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Author: mav Date: Thu Dec 18 08:46:53 2014 New Revision: 275895 URL: https://svnweb.freebsd.org/changeset/base/275895 Log: MFC r275568: Count consecutive read requests as blocking in CTL for files and ZVOLs. Technically read requests can be executed in any order or simultaneously since they are not changing any data. But ZFS prefetcher goes crasy when it receives consecutive requests from different threads. Since prefetcher works on level of separate blocks, instead of two consecutive 128K requests it may receive 32 8K requests in mixed order. This patch is more workaround then a real fix, and it does not fix all of prefetcher problems, but it improves sequential read speed by 3-4x times in some configurations. On the other side it may hurt performance if some backing store has no prefetch, that is why it is disabled by default for raw devices. Modified: stable/10/sys/cam/ctl/ctl.c stable/10/sys/cam/ctl/ctl_backend.h stable/10/sys/cam/ctl/ctl_backend_block.c stable/10/sys/cam/ctl/ctl_private.h stable/10/sys/cam/ctl/ctl_ser_table.c stable/10/usr.sbin/ctladm/ctladm.8 Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/cam/ctl/ctl.c ============================================================================== --- stable/10/sys/cam/ctl/ctl.c Thu Dec 18 08:45:28 2014 (r275894) +++ stable/10/sys/cam/ctl/ctl.c Thu Dec 18 08:46:53 2014 (r275895) @@ -435,7 +435,9 @@ static int ctl_inquiry_evpd_lbp(struct c static int ctl_inquiry_evpd(struct ctl_scsiio *ctsio); static int ctl_inquiry_std(struct ctl_scsiio *ctsio); static int ctl_get_lba_len(union ctl_io *io, uint64_t *lba, uint64_t *len); -static ctl_action ctl_extent_check(union ctl_io *io1, union ctl_io *io2); +static ctl_action ctl_extent_check(union ctl_io *io1, union ctl_io *io2, + bool seq); +static ctl_action ctl_extent_check_seq(union ctl_io *io1, union ctl_io *io2); static ctl_action ctl_check_for_blockage(struct ctl_lun *lun, union ctl_io *pending_io, union ctl_io *ooa_io); static ctl_action ctl_check_ooa(struct ctl_lun *lun, union ctl_io *pending_io, @@ -4592,6 +4594,17 @@ ctl_alloc_lun(struct ctl_softc *ctl_soft if (value != NULL && strcmp(value, "on") == 0) lun->flags |= CTL_LUN_READONLY; + lun->serseq = CTL_LUN_SERSEQ_OFF; + if (be_lun->flags & CTL_LUN_FLAG_SERSEQ_READ) + lun->serseq = CTL_LUN_SERSEQ_READ; + value = ctl_get_opt(&be_lun->options, "serseq"); + if (value != NULL && strcmp(value, "on") == 0) + lun->serseq = CTL_LUN_SERSEQ_ON; + else if (value != NULL && strcmp(value, "read") == 0) + lun->serseq = CTL_LUN_SERSEQ_READ; + else if (value != NULL && strcmp(value, "off") == 0) + lun->serseq = CTL_LUN_SERSEQ_OFF; + lun->ctl_softc = ctl_softc; TAILQ_INIT(&lun->ooa_queue); TAILQ_INIT(&lun->blocked_queue); @@ -10754,15 +10767,15 @@ ctl_get_lba_len(union ctl_io *io, uint64 } static ctl_action -ctl_extent_check_lba(uint64_t lba1, uint64_t len1, uint64_t lba2, uint64_t len2) +ctl_extent_check_lba(uint64_t lba1, uint64_t len1, uint64_t lba2, uint64_t len2, + bool seq) { uint64_t endlba1, endlba2; - endlba1 = lba1 + len1 - 1; + endlba1 = lba1 + len1 - (seq ? 0 : 1); endlba2 = lba2 + len2 - 1; - if ((endlba1 < lba2) - || (endlba2 < lba1)) + if ((endlba1 < lba2) || (endlba2 < lba1)) return (CTL_ACTION_PASS); else return (CTL_ACTION_BLOCK); @@ -10801,23 +10814,39 @@ ctl_extent_check_unmap(union ctl_io *io, } static ctl_action -ctl_extent_check(union ctl_io *io1, union ctl_io *io2) +ctl_extent_check(union ctl_io *io1, union ctl_io *io2, bool seq) { uint64_t lba1, lba2; uint64_t len1, len2; int retval; - if (ctl_get_lba_len(io1, &lba1, &len1) != 0) + if (ctl_get_lba_len(io2, &lba2, &len2) != 0) return (CTL_ACTION_ERROR); - retval = ctl_extent_check_unmap(io2, lba1, len1); + retval = ctl_extent_check_unmap(io1, lba2, len2); if (retval != CTL_ACTION_ERROR) return (retval); + if (ctl_get_lba_len(io1, &lba1, &len1) != 0) + return (CTL_ACTION_ERROR); + + return (ctl_extent_check_lba(lba1, len1, lba2, len2, seq)); +} + +static ctl_action +ctl_extent_check_seq(union ctl_io *io1, union ctl_io *io2) +{ + uint64_t lba1, lba2; + uint64_t len1, len2; + + if (ctl_get_lba_len(io1, &lba1, &len1) != 0) + return (CTL_ACTION_ERROR); if (ctl_get_lba_len(io2, &lba2, &len2) != 0) return (CTL_ACTION_ERROR); - return (ctl_extent_check_lba(lba1, len1, lba2, len2)); + if (lba1 + len1 == lba2) + return (CTL_ACTION_BLOCK); + return (CTL_ACTION_PASS); } static ctl_action @@ -10906,12 +10935,18 @@ ctl_check_for_blockage(struct ctl_lun *l case CTL_SER_BLOCK: return (CTL_ACTION_BLOCK); case CTL_SER_EXTENT: - return (ctl_extent_check(pending_io, ooa_io)); + return (ctl_extent_check(ooa_io, pending_io, + (lun->serseq == CTL_LUN_SERSEQ_ON))); case CTL_SER_EXTENTOPT: if ((lun->mode_pages.control_page[CTL_PAGE_CURRENT].queue_flags & SCP_QUEUE_ALG_MASK) != SCP_QUEUE_ALG_UNRESTRICTED) - return (ctl_extent_check(pending_io, ooa_io)); - /* FALLTHROUGH */ + return (ctl_extent_check(ooa_io, pending_io, + (lun->serseq == CTL_LUN_SERSEQ_ON))); + return (CTL_ACTION_PASS); + case CTL_SER_EXTENTSEQ: + if (lun->serseq != CTL_LUN_SERSEQ_OFF) + return (ctl_extent_check_seq(ooa_io, pending_io)); + return (CTL_ACTION_PASS); case CTL_SER_PASS: return (CTL_ACTION_PASS); case CTL_SER_BLOCKOPT: @@ -12442,7 +12477,7 @@ ctl_cmd_pattern_match(struct ctl_scsiio return (CTL_LUN_PAT_NONE); action = ctl_extent_check_lba(lba1, len1, desc->lba_range.lba, - desc->lba_range.len); + desc->lba_range.len, FALSE); /* * A "pass" means that the LBA ranges don't overlap, so * this doesn't match the user's range criteria. Modified: stable/10/sys/cam/ctl/ctl_backend.h ============================================================================== --- stable/10/sys/cam/ctl/ctl_backend.h Thu Dec 18 08:45:28 2014 (r275894) +++ stable/10/sys/cam/ctl/ctl_backend.h Thu Dec 18 08:46:53 2014 (r275895) @@ -85,7 +85,8 @@ typedef enum { CTL_LUN_FLAG_DEVID = 0x20, CTL_LUN_FLAG_DEV_TYPE = 0x40, CTL_LUN_FLAG_UNMAP = 0x80, - CTL_LUN_FLAG_OFFLINE = 0x100 + CTL_LUN_FLAG_OFFLINE = 0x100, + CTL_LUN_FLAG_SERSEQ_READ = 0x200 } ctl_backend_lun_flags; #ifdef _KERNEL Modified: stable/10/sys/cam/ctl/ctl_backend_block.c ============================================================================== --- stable/10/sys/cam/ctl/ctl_backend_block.c Thu Dec 18 08:45:28 2014 (r275894) +++ stable/10/sys/cam/ctl/ctl_backend_block.c Thu Dec 18 08:46:53 2014 (r275895) @@ -2207,6 +2207,8 @@ ctl_be_block_create(struct ctl_be_block_ be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_OFFLINE; if (unmap) be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_UNMAP; + if (be_lun->dispatch != ctl_be_block_dispatch_dev) + be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_SERSEQ_READ; be_lun->ctl_be_lun.be_lun = be_lun; be_lun->ctl_be_lun.maxlba = (be_lun->size_blocks == 0) ? 0 : (be_lun->size_blocks - 1); Modified: stable/10/sys/cam/ctl/ctl_private.h ============================================================================== --- stable/10/sys/cam/ctl/ctl_private.h Thu Dec 18 08:45:28 2014 (r275894) +++ stable/10/sys/cam/ctl/ctl_private.h Thu Dec 18 08:46:53 2014 (r275895) @@ -97,6 +97,7 @@ typedef enum { CTL_SER_BLOCKOPT, CTL_SER_EXTENT, CTL_SER_EXTENTOPT, + CTL_SER_EXTENTSEQ, CTL_SER_PASS, CTL_SER_SKIP } ctl_serialize_action; @@ -183,6 +184,12 @@ typedef enum { } ctl_lun_flags; typedef enum { + CTL_LUN_SERSEQ_OFF, + CTL_LUN_SERSEQ_READ, + CTL_LUN_SERSEQ_ON +} ctl_lun_serseq; + +typedef enum { CTLBLOCK_FLAG_NONE = 0x00, CTLBLOCK_FLAG_INVALID = 0x01 } ctlblock_flags; @@ -386,6 +393,7 @@ struct ctl_lun { struct ctl_id target; uint64_t lun; ctl_lun_flags flags; + ctl_lun_serseq serseq; STAILQ_HEAD(,ctl_error_desc) error_list; uint64_t error_serial; struct ctl_softc *ctl_softc; Modified: stable/10/sys/cam/ctl/ctl_ser_table.c ============================================================================== --- stable/10/sys/cam/ctl/ctl_ser_table.c Thu Dec 18 08:45:28 2014 (r275894) +++ stable/10/sys/cam/ctl/ctl_ser_table.c Thu Dec 18 08:46:53 2014 (r275895) @@ -59,12 +59,13 @@ #define bO CTL_SER_BLOCKOPT /* Optional block */ #define xT CTL_SER_EXTENT /* Extent check */ #define xO CTL_SER_EXTENTOPT /* Optional extent check */ +#define xS CTL_SER_EXTENTSEQ /* Sequential extent check */ static ctl_serialize_action ctl_serialize_table[CTL_SERIDX_COUNT][CTL_SERIDX_COUNT] = { /**>IDX_ :: 2nd:TUR RD WRT UNM MDSN MDSL RQSN INQ RDCP RES LSNS FMT STR*/ /*TUR */{ pS, pS, pS, pS, bK, bK, bK, pS, pS, bK, pS, bK, bK}, -/*READ */{ pS, pS, xT, bO, bK, bK, bK, pS, pS, bK, pS, bK, bK}, +/*READ */{ pS, xS, xT, bO, bK, bK, bK, pS, pS, bK, pS, bK, bK}, /*WRITE */{ pS, xT, xT, bO, bK, bK, bK, pS, pS, bK, pS, bK, bK}, /*UNMAP */{ pS, xO, xO, pS, bK, bK, bK, pS, pS, bK, pS, bK, bK}, /*MD_SNS */{ bK, bK, bK, bK, pS, bK, bK, pS, pS, bK, pS, bK, bK}, Modified: stable/10/usr.sbin/ctladm/ctladm.8 ============================================================================== --- stable/10/usr.sbin/ctladm/ctladm.8 Thu Dec 18 08:45:28 2014 (r275894) +++ stable/10/usr.sbin/ctladm/ctladm.8 Thu Dec 18 08:46:53 2014 (r275895) @@ -34,7 +34,7 @@ .\" $Id: //depot/users/kenm/FreeBSD-test2/usr.sbin/ctladm/ctladm.8#3 $ .\" $FreeBSD$ .\" -.Dd November 5, 2014 +.Dd December 6, 2014 .Dt CTLADM 8 .Os .Sh NAME @@ -995,6 +995,13 @@ command sequence order shall be explicit client through the selection of appropriate commands and task attributes. The default value is "restricted". It improves data integrity, but may introduce some additional delays. +.It Va serseq +Set to "on" to serialize conseсutive reads/writes. +Set to "read" to serialize conseсutive reads. +Set to "off" to allow them be issued in parallel. +Parallel issue of consecutive operations may confuse logic of the +backing file system, hurting performance; but it may improve performance +of backing stores without prefetch/write-back. .It Va rpm Specifies medium rotation rate of the device: 0 -- not reported, 1 -- non-rotating (SSD), >1024 -- value in revolutions per minute.
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