From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DBDB5C33CB1 for ; Fri, 17 Jan 2020 14:45:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A41512073A for ; Fri, 17 Jan 2020 14:45:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726957AbgAQOpa (ORCPT ); Fri, 17 Jan 2020 09:45:30 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:22046 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726827AbgAQOpa (ORCPT ); Fri, 17 Jan 2020 09:45:30 -0500 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00HEeMcE131091 for ; Fri, 17 Jan 2020 09:45:26 -0500 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xk0qrqtym-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 17 Jan 2020 09:45:26 -0500 Received: from localhost by e06smtp01.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 17 Jan 2020 14:45:21 -0000 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 00HEiVMb50332102 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jan 2020 14:44:31 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A7D394204F; Fri, 17 Jan 2020 14:45:20 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5276142045; Fri, 17 Jan 2020 14:45:19 +0000 (GMT) Received: from localhost.localdomain (unknown [9.85.97.235]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jan 2020 14:45:19 +0000 (GMT) From: Chandan Rajendra To: "Darrick J. Wong" Cc: david@fromorbit.com, Chandan Rajendra , linux-xfs@vger.kernel.org Subject: Re: [PATCH V2 2/2] xfs: Fix log reservation calculation for xattr insert operation Date: Fri, 17 Jan 2020 20:17:55 +0530 Organization: IBM In-Reply-To: <2258200.WESrQN0qAt@localhost.localdomain> References: <20200115125421.22719-1-chandanrlinux@gmail.com> <20200117004618.GO8247@magnolia> <2258200.WESrQN0qAt@localhost.localdomain> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-TM-AS-GCONF: 00 x-cbid: 20011714-4275-0000-0000-00000398863A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20011714-4276-0000-0000-000038AC87E5 Message-Id: <3798161.AAjsAJd4dB@localhost.localdomain> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-01-17_03:2020-01-16,2020-01-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 malwarescore=0 phishscore=0 mlxscore=0 bulkscore=0 impostorscore=0 priorityscore=1501 clxscore=1015 lowpriorityscore=0 adultscore=0 spamscore=0 suspectscore=2 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001170115 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Friday, January 17, 2020 10:16 AM Chandan Rajendra wrote: > On Friday, January 17, 2020 6:16 AM Darrick J. Wong wrote: > > On Wed, Jan 15, 2020 at 06:24:21PM +0530, Chandan Rajendra wrote: > > > Log space reservation for xattr insert operation can be divided into two > > > parts, > > > 1. Mount time > > > - Inode > > > - Superblock for accounting space allocations > > > - AGF for accounting space used be count, block number, rmapbt and refcnt > > > btrees. > > > > > > 2. The remaining log space can only be calculated at run time because, > > > - A local xattr can be large enough to cause a double split of the dabtree. > > > - The value of the xattr can be large enough to be stored in remote > > > blocks. The contents of the remote blocks are not logged. > > > > > > The log space reservation could be, > > > - 2 * XFS_DA_NODE_MAXDEPTH number of blocks. Additional XFS_DA_NODE_MAXDEPTH > > > number of blocks are required if xattr is large enough to cause another > > > split of the dabtree path from root to leaf block. > > > - BMBT blocks for storing (2 * XFS_DA_NODE_MAXDEPTH) record > > > entries. Additional XFS_DA_NODE_MAXDEPTH number of blocks are required in > > > case of a double split of the dabtree path from root to leaf blocks. > > > - Space for logging blocks of count, block number, rmap and refcnt btrees. > > > > > > Presently, mount time log reservation includes block count required for a > > > single split of the dabtree. The dabtree block count is also taken into > > > account by xfs_attr_calc_size(). > > > > > > Also, AGF log space reservation isn't accounted for. Hence log reservation > > > calculation for xattr insert operation gives incorrect value. > > > > > > Apart from the above, xfs_log_calc_max_attrsetm_res() passes a byte count as > > > an argument to XFS_NEXTENTADD_SPACE_RES() instead of block count. > > > > > > To fix these issues, this commit refactors xfs_attr_calc_size() to calculate, > > > 1. The number of dabtree blocks that need to be logged. > > > 2. The number of remote blocks that need to allocated. > > > 3. The number of dabtree blocks that need to allocated. > > > > > > xfs_attr_set() uses this information to compute > > > 1. Number of blocks that needs to allocated during the transaction. > > > 2. Number of bytes that needs to be reserved in the log. > > > > > > This commit also modifies xfs_log_calc_max_attrsetm_res() to invoke > > > xfs_attr_calc_size() to obtain the number of dabtree blocks to be > > > logged which it uses to figure out the total number of blocks to be logged. > > > > > > Signed-off-by: Chandan Rajendra > > > --- > > > Changelog: > > > V1 -> V2: > > > 1. xfs_attr_calc_size() computes > > > - Number of blocks required to log dabtree blocks. > > > - Number of remote blocks. > > > - Total dabtree blocks to be allocated. > > > 2. Add new function xfs_calc_attr_blocks() to compute the total number of > > > blocks to be allocated during xattr insert operation. > > > 3. Add new function xfs_calc_attr_res() to compute the log space to be > > > reserved during xattr insert operation. > > > > > > fs/xfs/libxfs/xfs_attr.c | 108 +++++++++++++++++++++------------ > > > fs/xfs/libxfs/xfs_attr.h | 3 + > > > fs/xfs/libxfs/xfs_log_rlimit.c | 17 +++--- > > > fs/xfs/libxfs/xfs_trans_resv.c | 56 +++++++++-------- > > > fs/xfs/libxfs/xfs_trans_resv.h | 2 + > > > 5 files changed, 113 insertions(+), 73 deletions(-) > > > > > > diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > > > index 1eae1db74f6c..363b4c47b134 100644 > > > --- a/fs/xfs/libxfs/xfs_attr.c > > > +++ b/fs/xfs/libxfs/xfs_attr.c > > > @@ -183,43 +183,6 @@ xfs_attr_get( > > > return 0; > > > } > > > > > > -/* > > > - * Calculate how many blocks we need for the new attribute, > > > - */ > > > -STATIC int > > > -xfs_attr_calc_size( > > > - struct xfs_da_args *args, > > > - int *local) > > > -{ > > > - struct xfs_mount *mp = args->dp->i_mount; > > > - int size; > > > - int nblks; > > > - > > > - /* > > > - * Determine space new attribute will use, and if it would be > > > - * "local" or "remote" (note: local != inline). > > > - */ > > > - size = xfs_attr_leaf_newentsize(mp, args->namelen, args->valuelen, > > > - local); > > > - nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK); > > > - if (*local) { > > > - if (size > (args->geo->blksize / 2)) { > > > - /* Double split possible */ > > > - nblks *= 2; > > > - } > > > - } else { > > > - /* > > > - * Out of line attribute, cannot double split, but > > > - * make room for the attribute value itself. > > > - */ > > > - uint dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen); > > > - nblks += dblocks; > > > - nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK); > > > - } > > > - > > > - return nblks; > > > -} > > > - > > > STATIC int > > > xfs_attr_try_sf_addname( > > > struct xfs_inode *dp, > > > @@ -248,6 +211,64 @@ xfs_attr_try_sf_addname( > > > return error ? error : error2; > > > } > > > > > > +STATIC uint > > > +xfs_calc_attr_blocks( > > > + struct xfs_mount *mp, > > > + unsigned int total_dablks, > > > + unsigned int rmt_blks) > > > +{ > > > + unsigned int bmbt_blks; > > > + > > > + bmbt_blks = XFS_NEXTENTADD_SPACE_RES(mp, total_dablks + rmt_blks, > > > + XFS_ATTR_FORK); > > > + return total_dablks + rmt_blks + bmbt_blks; > > > > I think this calculation could be added to xfs_attr_calc_size and passed > > back to the caller as another outparam. > > > > At this point we have five different block counts I'm wondering if we > > should create a struct and pass it around... > > > > > +} > > > + > > > +/* > > > + * Calculate how many blocks we need for the new attribute, > > > + */ > > > +void > > > +xfs_attr_calc_size( > > > + struct xfs_mount *mp, > > > + int namelen, > > > + int valuelen, > > > + int *local, > > > + unsigned int *log_dablks, > > > + unsigned int *rmt_blks, > > > + unsigned int *total_dablks) > > > > ...something like this? It'll be much easier to remember what each of > > those parameters actually do with a full sentence comment: > > > > struct xfs_attr_set_resv { > > /* Number of blocks in the da btree that we might need to log. */ > > unsigned int log_dablks; > > > > /* Number of unlogged blocks needed to store the remote attr value. */ > > unsigned int rmt_blks; > > > > /* Blocks we might need to map into the attribute fork. */ > > unsigned int total_dablks; > > > > /* Blocks we might need to allocate. */ > > unsigned int alloc_blks; > > > > /* Blocks we might need to create all the new attr fork mappings. */ > > unsigned int bmbt_blks; > > }; > > > > > +{ > > > + unsigned int blksize; > > > + int size; > > > + > > > + blksize = mp->m_dir_geo->blksize; > > > + *log_dablks = 0; > > > + *rmt_blks = 0; > > > + *total_dablks = 0; > > > > No need to zero out variables that we're going to set two lines later. > > > > > + > > > + /* > > > + * Determine space new attribute will use, and if it would be > > > + * "local" or "remote" (note: local != inline). > > > + */ > > > + size = xfs_attr_leaf_newentsize(mp, namelen, valuelen, local); > > > + > > > + *total_dablks = XFS_DAENTER_BLOCKS(mp, XFS_ATTR_FORK); > > > + *log_dablks = 2 * *total_dablks; > > > + > > > + if (*local) { > > > + if (size > (blksize / 2)) { > > > + /* Double split possible */ > > > + *log_dablks += *total_dablks; > > > + *total_dablks *= 2; > > > + } > > > + } else { > > > + /* > > > + * Out of line attribute, cannot double split, but > > > + * make room for the attribute value itself. > > > + */ > > > + *rmt_blks = xfs_attr3_rmt_blocks(mp, valuelen); > > > + } > > > +} > > > + > > > /* > > > * Set the attribute specified in @args. > > > */ > > > @@ -346,6 +367,9 @@ xfs_attr_set( > > > struct xfs_mount *mp = dp->i_mount; > > > struct xfs_da_args args; > > > struct xfs_trans_res tres; > > > + unsigned int log_dablks; > > > + unsigned int rmt_blks; > > > + unsigned int total_dablks; > > > int rsvd = (flags & ATTR_ROOT) != 0; > > > int error, local; > > > > > > @@ -361,7 +385,11 @@ xfs_attr_set( > > > args.value = value; > > > args.valuelen = valuelen; > > > args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT; > > > - args.total = xfs_attr_calc_size(&args, &local); > > > + > > > + xfs_attr_calc_size(mp, args.namelen, args.valuelen, &local, > > > + &log_dablks, &rmt_blks, &total_dablks); > > > + > > > + args.total = xfs_calc_attr_blocks(mp, total_dablks, rmt_blks); > > > > > > error = xfs_qm_dqattach(dp); > > > if (error) > > > @@ -380,8 +408,8 @@ xfs_attr_set( > > > return error; > > > } > > > > > > - tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres + > > > - M_RES(mp)->tr_attrsetrt.tr_logres * args.total; > > > + tres.tr_logres = xfs_calc_attr_res(mp, log_dablks, rmt_blks, > > > + total_dablks); > > > tres.tr_logcount = XFS_ATTRSET_LOG_COUNT; > > > tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; > > > > > > diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h > > > index 94badfa1743e..a1c77618802b 100644 > > > --- a/fs/xfs/libxfs/xfs_attr.h > > > +++ b/fs/xfs/libxfs/xfs_attr.h > > > @@ -154,5 +154,8 @@ int xfs_attr_remove_args(struct xfs_da_args *args); > > > int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize, > > > int flags, struct attrlist_cursor_kern *cursor); > > > bool xfs_attr_namecheck(const void *name, size_t length); > > > +void xfs_attr_calc_size(struct xfs_mount *mp, int namelen, int valuelen, > > > + int *local, unsigned int *log_dablks, > > > + unsigned int *rmt_blks, unsigned int *total_dablks); > > > > > > #endif /* __XFS_ATTR_H__ */ > > > diff --git a/fs/xfs/libxfs/xfs_log_rlimit.c b/fs/xfs/libxfs/xfs_log_rlimit.c > > > index 7f55eb3f3653..33b805411f72 100644 > > > --- a/fs/xfs/libxfs/xfs_log_rlimit.c > > > +++ b/fs/xfs/libxfs/xfs_log_rlimit.c > > > @@ -10,6 +10,7 @@ > > > #include "xfs_log_format.h" > > > #include "xfs_trans_resv.h" > > > #include "xfs_mount.h" > > > +#include "xfs_attr.h" > > > #include "xfs_da_format.h" > > > #include "xfs_trans_space.h" > > > #include "xfs_da_btree.h" > > > @@ -23,17 +24,19 @@ STATIC int > > > xfs_log_calc_max_attrsetm_res( > > > struct xfs_mount *mp) > > > { > > > - int size; > > > - int nblks; > > > + int size; > > > + int local; > > > + unsigned int total_dablks; > > > + unsigned int rmt_blks; > > > + unsigned int log_dablks; > > > > > > size = xfs_attr_leaf_entsize_local_max(mp->m_attr_geo->blksize) - > > > MAXNAMELEN - 1; > > > - nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK); > > > - nblks += XFS_B_TO_FSB(mp, size); > > > - nblks += XFS_NEXTENTADD_SPACE_RES(mp, size, XFS_ATTR_FORK); > > > + xfs_attr_calc_size(mp, size, 0, &local, &log_dablks, &rmt_blks, > > > + &total_dablks); > > > + ASSERT(local == 1); > > > > > > - return M_RES(mp)->tr_attrsetm.tr_logres + > > > - M_RES(mp)->tr_attrsetrt.tr_logres * nblks; > > > + return xfs_calc_attr_res(mp, log_dablks, rmt_blks, total_dablks); > > > } > > > > > > /* > > > diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c > > > index 824073a839ac..8a0fea655358 100644 > > > --- a/fs/xfs/libxfs/xfs_trans_resv.c > > > +++ b/fs/xfs/libxfs/xfs_trans_resv.c > > > @@ -701,12 +701,10 @@ xfs_calc_attrinval_reservation( > > > * Setting an attribute at mount time. > > > * the inode getting the attribute > > > * the superblock for allocations > > > - * the agfs extents are allocated from > > > - * the attribute btree * max depth > > > - * the inode allocation btree > > > + * the agf extents are allocated from > > > * Since attribute transaction space is dependent on the size of the attribute, > > > * the calculation is done partially at mount time and partially at runtime(see > > > - * below). > > > + * xfs_attr_calc_size()). > > > */ > > > STATIC uint > > > xfs_calc_attrsetm_reservation( > > > @@ -714,27 +712,7 @@ xfs_calc_attrsetm_reservation( > > > { > > > return XFS_DQUOT_LOGRES(mp) + > > > xfs_calc_inode_res(mp, 1) + > > > - xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) + > > > - xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH, XFS_FSB_TO_B(mp, 1)); > > > -} > > > - > > > -/* > > > - * Setting an attribute at runtime, transaction space unit per block. > > > - * the superblock for allocations: sector size > > > - * the inode bmap btree could join or split: max depth * block size > > > - * Since the runtime attribute transaction space is dependent on the total > > > - * blocks needed for the 1st bmap, here we calculate out the space unit for > > > - * one block so that the caller could figure out the total space according > > > - * to the attibute extent length in blocks by: > > > - * ext * M_RES(mp)->tr_attrsetrt.tr_logres > > > - */ > > > -STATIC uint > > > -xfs_calc_attrsetrt_reservation( > > > - struct xfs_mount *mp) > > > -{ > > > - return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) + > > > - xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK), > > > - XFS_FSB_TO_B(mp, 1)); > > > + xfs_calc_buf_res(2, mp->m_sb.sb_sectsize); > > > > What effect does changing these reservation calculations have on the > > computed minimum log size? > > > > > } > > > > > > /* > > > @@ -832,6 +810,32 @@ xfs_calc_sb_reservation( > > > return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize); > > > } > > > > > > +uint > > > +xfs_calc_attr_res( > > > + struct xfs_mount *mp, > > > + unsigned int log_dablks, > > > + unsigned int rmt_blks, > > > + unsigned int total_dablks) > > > +{ > > > + unsigned int da_blksize; > > > + unsigned int fs_blksize; > > > + unsigned int bmbt_blks; > > > + unsigned int space_blks; > > > + > > > + bmbt_blks = XFS_NEXTENTADD_SPACE_RES(mp, total_dablks + rmt_blks, > > > + XFS_ATTR_FORK); > > > > Pass in the resv structure above and you won't need to calculate this > > again. > > > > > + space_blks = xfs_allocfree_log_count(mp, > > > + total_dablks + rmt_blks + bmbt_blks); > > > > Only two levels of indent needed here: > > > > space_blks = xfs_allocfree_log_count(mp, > > total_dablks + rmt_blks + bmbt_blks); > > > > > + > > > + da_blksize = mp->m_attr_geo->blksize; > > > + fs_blksize = mp->m_sb.sb_blocksize; > > > > You could probably pass these to xfs_calc_buf_res directly. > > > > I'll give this a spin and see how it does. > > > > --D > > > > > + > > > + return M_RES(mp)->tr_attrsetm.tr_logres + > > > + xfs_calc_buf_res(log_dablks, da_blksize) + > > > + xfs_calc_buf_res(bmbt_blks, fs_blksize) + > > > + xfs_calc_buf_res(space_blks, fs_blksize); > > > +} > > > + > > > void > > > xfs_trans_resv_calc( > > > struct xfs_mount *mp, > > > @@ -942,7 +946,7 @@ xfs_trans_resv_calc( > > > resp->tr_ichange.tr_logres = xfs_calc_ichange_reservation(mp); > > > resp->tr_fsyncts.tr_logres = xfs_calc_swrite_reservation(mp); > > > resp->tr_writeid.tr_logres = xfs_calc_writeid_reservation(mp); > > > - resp->tr_attrsetrt.tr_logres = xfs_calc_attrsetrt_reservation(mp); > > > + resp->tr_attrsetrt.tr_logres = 0; > > > resp->tr_clearagi.tr_logres = xfs_calc_clear_agi_bucket_reservation(mp); > > > resp->tr_growrtzero.tr_logres = xfs_calc_growrtzero_reservation(mp); > > > resp->tr_growrtfree.tr_logres = xfs_calc_growrtfree_reservation(mp); > > > diff --git a/fs/xfs/libxfs/xfs_trans_resv.h b/fs/xfs/libxfs/xfs_trans_resv.h > > > index 7241ab28cf84..48ceba72fb12 100644 > > > --- a/fs/xfs/libxfs/xfs_trans_resv.h > > > +++ b/fs/xfs/libxfs/xfs_trans_resv.h > > > @@ -91,6 +91,8 @@ struct xfs_trans_resv { > > > #define XFS_ATTRSET_LOG_COUNT 3 > > > #define XFS_ATTRRM_LOG_COUNT 3 > > > > > > +uint xfs_calc_attr_res(struct xfs_mount *mp, unsigned int log_dablks, > > > + unsigned int rmt_blks, unsigned int total_dablks); > > > void xfs_trans_resv_calc(struct xfs_mount *mp, struct xfs_trans_resv *resp); > > > uint xfs_allocfree_log_count(struct xfs_mount *mp, uint num_ops); > > > > > > > Hi Darrick, > > I agree to the changes you have suggested. I will apply them and post the next > version soon. > > I will also figure out the effect of this patch on minimum log size. > Darrick, The log space reservation numbers mentioned in response to one of the of earlier mails were not correct. I had misinterpreted tr_logres to be in units of blocks when doing calculations. Here are the correct numbers, Without patch ------------- xattr log reservation space = 555768 With patch ---------- xattr log reservation space = 834936 The changes in xattr log space reservation numbers do not have any effect on minimum log size calculation. This is because log reservation for truncate operation is much larger; i.e tr_logres = 259968, tr_logcount = 8, tr_logflags = 4 ... which would be 259968 * 8 = 2079744 bytes Since 2079744 > 834936, the rest of the calculation for minimum log reservation does not change. -- chandan