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### This file controls the configuration of the FSFS filesystem.
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[memcached-servers]
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### These options name memcached servers used to cache internal FSFS
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### data.  See http://www.danga.com/memcached/ for more information on
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### memcached.  To use memcached with FSFS, run one or more memcached
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### servers, and specify each of them as an option like so:
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# first-server = 127.0.0.1:11211
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# remote-memcached = mymemcached.corp.example.com:11212
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### The option name is ignored; the value is of the form HOST:PORT.
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### memcached servers can be shared between multiple repositories;
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### however, if you do this, you *must* ensure that repositories have
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### distinct UUIDs and paths, or else cached data from one repository
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### might be used by another accidentally.  Note also that memcached has
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### no authentication for reads or writes, so you must ensure that your
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### memcached servers are only accessible by trusted users.
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[caches]
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### When a cache-related error occurs, normally Subversion ignores it
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### and continues, logging an error if the server is appropriately
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### configured (and ignoring it with file:// access).  To make
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### Subversion never ignore cache errors, uncomment this line.
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# fail-stop = true
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[rep-sharing]
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### To conserve space, the filesystem can optionally avoid storing
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### duplicate representations.  This comes at a slight cost in
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### performance, as maintaining a database of shared representations can
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### increase commit times.  The space savings are dependent upon the size
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### of the repository, the number of objects it contains and the amount of
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### duplication between them, usually a function of the branching and
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### merging process.
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###
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### The following parameter enables rep-sharing in the repository.  It can
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### be switched on and off at will, but for best space-saving results
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### should be enabled consistently over the life of the repository.
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### 'svnadmin verify' will check the rep-cache regardless of this setting.
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### rep-sharing is enabled by default.
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# enable-rep-sharing = true
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[deltification]
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### To conserve space, the filesystem stores data as differences against
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### existing representations.  This comes at a slight cost in performance,
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### as calculating differences can increase commit times.  Reading data
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### will also create higher CPU load and the data will be fragmented.
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### Since deltification tends to save significant amounts of disk space,
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### the overall I/O load can actually be lower.
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###
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### The options in this section allow for tuning the deltification
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### strategy.  Their effects on data size and server performance may vary
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### from one repository to another.  Versions prior to 1.8 will ignore
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### this section.
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###
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### The following parameter enables deltification for directories. It can
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### be switched on and off at will, but for best space-saving results
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### should be enabled consistently over the lifetime of the repository.
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### Repositories containing large directories will benefit greatly.
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### In rarely accessed repositories, the I/O overhead may be significant
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### as caches will most likely be low.
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### directory deltification is enabled by default.
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# enable-dir-deltification = true
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###
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### The following parameter enables deltification for properties on files
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### and directories.  Overall, this is a minor tuning option but can save
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### some disk space if you merge frequently or frequently change node
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### properties.  You should not activate this if rep-sharing has been
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### disabled because this may result in a net increase in repository size.
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### property deltification is enabled by default.
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# enable-props-deltification = true
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###
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### During commit, the server may need to walk the whole change history of
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### of a given node to find a suitable deltification base.  This linear
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### process can impact commit times, svnadmin load and similar operations.
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### This setting limits the depth of the deltification history.  If the
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### threshold has been reached, the node will be stored as fulltext and a
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### new deltification history begins.
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### Note, this is unrelated to svn log.
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### Very large values rarely provide significant additional savings but
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### can impact performance greatly - in particular if directory
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### deltification has been activated.  Very small values may be useful in
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### repositories that are dominated by large, changing binaries.
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### Should be a power of two minus 1.  A value of 0 will effectively
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### disable deltification.
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### For 1.8, the default value is 1023; earlier versions have no limit.
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# max-deltification-walk = 1023
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###
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### The skip-delta scheme used by FSFS tends to repeatably store redundant
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### delta information where a simple delta against the latest version is
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### often smaller.  By default, 1.8+ will therefore use skip deltas only
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### after the linear chain of deltas has grown beyond the threshold
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### specified by this setting.
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### Values up to 64 can result in some reduction in repository size for
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### the cost of quickly increasing I/O and CPU costs. Similarly, smaller
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### numbers can reduce those costs at the cost of more disk space.  For
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### rarely read repositories or those containing larger binaries, this may
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### present a better trade-off.
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### Should be a power of two.  A value of 1 or smaller will cause the
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### exclusive use of skip-deltas (as in pre-1.8).
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### For 1.8, the default value is 16; earlier versions use 1.
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# max-linear-deltification = 16
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###
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### After deltification, we compress the data through zlib to minimize on-
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### disk size.  That can be an expensive and ineffective process.  This
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### setting controls the usage of zlib in future revisions.
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### Revisions with highly compressible data in them may shrink in size
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### if the setting is increased but may take much longer to commit.  The
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### time taken to uncompress that data again is widely independent of the
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### compression level.
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### Compression will be ineffective if the incoming content is already
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### highly compressed.  In that case, disabling the compression entirely
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### will speed up commits as well as reading the data.  Repositories with
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### many small compressible files (source code) but also a high percentage
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### of large incompressible ones (artwork) may benefit from compression
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### levels lowered to e.g. 1.
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### Valid values are 0 to 9 with 9 providing the highest compression ratio
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### and 0 disabling it altogether.
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### The default value is 5.
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# compression-level = 5
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[packed-revprops]
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### This parameter controls the size (in kBytes) of packed revprop files.
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### Revprops of consecutive revisions will be concatenated into a single
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### file up to but not exceeding the threshold given here.  However, each
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### pack file may be much smaller and revprops of a single revision may be
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### much larger than the limit set here.  The threshold will be applied
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### before optional compression takes place.
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### Large values will reduce disk space usage at the expense of increased
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### latency and CPU usage reading and changing individual revprops.
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### Values smaller than 4 kByte will not improve latency any further and
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### quickly render revprop packing ineffective.
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### revprop-pack-size is 4 kBytes by default for non-compressed revprop
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### pack files and 16 kBytes when compression has been enabled.
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# revprop-pack-size = 4
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###
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### To save disk space, packed revprop files may be compressed.  Standard
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### revprops tend to allow for very effective compression.  Reading and
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### even more so writing, become significantly more CPU intensive.
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### Compressing packed revprops is disabled by default.
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# compress-packed-revprops = false
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[io]
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### Parameters in this section control the data access granularity in
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### format 7 repositories and later.  The defaults should translate into
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### decent performance over a wide range of setups.
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###
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### When a specific piece of information needs to be read from disk,  a
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### data block is being read at once and its contents are being cached.
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### If the repository is being stored on a RAID, the block size should be
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### either 50% or 100% of RAID block size / granularity.  Also, your file
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### system blocks/clusters should be properly aligned and sized.  In that
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### setup, each access will hit only one disk (minimizes I/O load) but
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### uses all the data provided by the disk in a single access.
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### For SSD-based storage systems, slightly lower values around 16 kB
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### may improve latency while still maximizing throughput.  If block-read
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### has not been enabled, this will be capped to 4 kBytes.
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### Can be changed at any time but must be a power of 2.
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### block-size is given in kBytes and with a default of 64 kBytes.
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# block-size = 64
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###
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### The log-to-phys index maps data item numbers to offsets within the
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### rev or pack file.  This index is organized in pages of a fixed maximum
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### capacity.  To access an item, the page table and the respective page
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### must be read.
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### This parameter only affects revisions with thousands of changed paths.
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### If you have several extremely large revisions (~1 mio changes), think
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### about increasing this setting.  Reducing the value will rarely result
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### in a net speedup.
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### This is an expert setting.  Must be a power of 2.
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### l2p-page-size is 8192 entries by default.
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# l2p-page-size = 8192
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###
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### The phys-to-log index maps positions within the rev or pack file to
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### to data items,  i.e. describes what piece of information is being
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### stored at any particular offset.  The index describes the rev file
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### in chunks (pages) and keeps a global list of all those pages.  Large
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### pages mean a shorter page table but a larger per-page description of
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### data items in it.  The latency sweetspot depends on the change size
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### distribution but covers a relatively wide range.
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### If the repository contains very large files,  i.e. individual changes
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### of tens of MB each,  increasing the page size will shorten the index
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### file at the expense of a slightly increased latency in sections with
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### smaller changes.
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### For source code repositories, this should be about 16x the block-size.
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### Must be a power of 2.
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### p2l-page-size is given in kBytes and with a default of 1024 kBytes.
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# p2l-page-size = 1024